0001514416-24-000024 | 10-K | XBRL Viewer

Print Document View Excel Document

Debt - ASU Adoption (Details) - USD ($) $ in Thousands	12 Months Ended
Debt - ASU Adoption (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Jan. 01, 2022
Debt Instrument [Line Items]
Interest expense, debt	$ 3,719	$ 5,224
Accumulated deficit	64,890	48,547
Additional paid-in capital	(391,048)	(364,913)
Deferred tax liability	(33,021)	(38,466)
Convertible senior notes	418,526	480,546
Cumulative effect of adoption, adjusted balance \| Accounting Standards Update 2020-06
Debt Instrument [Line Items]
Interest expense, debt	$ 29,200	$ 27,200
Accumulated deficit			$ 8,800
Additional paid-in capital			156,200
Deferred tax liability			1,000
Convertible senior notes			$ 148,400

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482900/835-30-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69B

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69C
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69C

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69E

Reference 8: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69F
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69F

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1D

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1D

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1D

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1F

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1F

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1F

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1F

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Basic and Diluted (Loss) Income per Common Share - Schedule of Antidilutive Common Share Equivalents Excluded from Earnings Per Share (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Feb. 28, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	9,451,503	2,766,847	1,511,844
2026 Convertible Notes \| Convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Conversion price (in usd per share)			$ 91.03		$ 91.03
2028 Convertible Notes \| Convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Conversion price (in usd per share)			$ 179.27	$ 179.27
Stock options issued and outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	97,480	159,741	180,209
Nonvested restricted stock units issued and outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	5,911,794	2,607,106	344,486
Convertible senior notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	3,442,229	0	987,149

Financial Statement Components - Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financial Statement Components [Abstract]
Accrued expense	$ 40,731	$ 29,990
Accrued compensation and benefits	19,142	21,595
Accrued sales, use, VAT and telecommunications related taxes	8,467	7,799
Income tax payable	0	2,235
Other accrued expenses	674	958
Total accrued expenses and other current liabilities	$ 69,014	$ 62,577

Fair Value Measurements

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair Value Measurements

The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable and accrued expenses approximate fair value as of December 31, 2023 and 2022 because of the relatively short duration of these instruments. Marketable securities consist of time deposits, corporate debt securities, U.S. treasury securities, and commercial paper not otherwise classified as cash equivalents. All marketable securities are considered to be available-for-sale and are recorded at their estimated fair values. Unrealized gains and losses for available-for-sale securities are recorded in accumulated other comprehensive loss.

The Company evaluated its financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level in which to classify them for each reporting period. The following tables summarize the Company’s financial assets measured at fair value as of December 31, 2023 and 2022:


	Amortized cost or carrying value		Unrealized gains		Unrealized losses		Fair value measurements on a recurring basis December 31, 2023
							Level 1		Level 2		Level 3		Total

	(In thousands)
Financial assets:
Cash and cash equivalents:
Money market account	$	120,724	$	—	$	—	$	120,724	$	—	$	—	$	120,724







Total included in cash and cash equivalents	120,724		—		—		120,724		—		—		120,724
Marketable securities:
Time deposits	20,000		—		—		20,000		—		—		20,000


Commercial paper	1,422		66		—		1,488		—		—		1,488
Total marketable securities	21,422		66		—		21,488		—		—		21,488



Total financial assets	$	142,146	$	66	$	—	$	142,212	$	—	$	—	$	142,212


	Amortized cost or carrying value		Unrealized gains		Unrealized losses		Fair value measurements on a recurring basis December 31, 2022
							Level 1		Level 2		Level 3		Total

	(In thousands)
Financial assets:
Cash and cash equivalents:
Money market account	$	36,728	$	—	$	—	$	36,728	$	—	$	—	$	36,728





Commercial paper	28,254		—		—		28,254		—		—		28,254

Total included in cash and cash equivalents	64,982		—		—		64,982		—		—		64,982
Marketable securities:
Time deposits	6,645		—		(15)		6,630		—		—		6,630
U.S. treasury securities	14,718		74		—		14,792		—		—		14,792
Corporate debt securities	23,412		—		(97)		—		23,315		—		23,315
Commercial paper	26,142		352		—		26,494		—		—		26,494
Total marketable securities	70,917		426		(112)		47,916		23,315		—		71,231



Total financial assets	$	135,899	$	426	$	(112)	$	112,898	$	23,315	$	—	$	136,213

The Company classifies its marketable securities as current assets as they are available for current operating needs. The following table summarizes the contractual maturities of marketable securities as of December 31, 2023:


	Amortized cost		Aggregate fair value

	(In thousands)
Financial assets:
Less than one year	$	21,422	$	21,488

Total	$	21,422	$	21,488

As of December 31, 2023, the marketable securities were in an unrealized gain position. The Company has determined that (i) it does not have the intent to sell any of these investments and (ii) it is not more likely than not that it will be required to sell any of these investments before recovery of the entire amortized cost basis. As of December 31, 2023, the Company anticipates that it will recover the entire amortized cost basis of its marketable securities before maturity.

During the years ended December 31, 2023 and 2022, there were $91.8 million and $74.3 million, respectively, in maturities of marketable securities. There were no maturities in marketable securities during the year ended December 31, 2021.

Proceeds from sales of marketable securities were $38.3 million and $34.4 million for the years ended December 31, 2023 and 2022, respectively. There were no sales in marketable securities during the year ended December 31, 2021.

Interest earned on marketable securities was $2.0 million and $1.2 million for the years ended December 31, 2023 and 2022, respectively. There was no interest earned on marketable securities during the year ended December 31, 2021. The interest is recorded in other income (expense), net, on the accompanying consolidated statements of operations. As of December 31, 2023 and 2022, the accrued interest receivable, net of allowance for credit losses, was $0.3 million. Accrued interest receivable is recorded in prepaid expenses and other current assets on the accompanying consolidated balance sheets.

As of December 31, 2023, the fair value of the 2026 Convertible Notes and 2028 Convertible Notes, as further described in Note 8, “Debt,” to these consolidated financial statements, was approximately $145.5 million and $157.6 million, respectively. As of December 31, 2022, the fair value of the 2026 Convertible Notes and the 2028 Convertible Notes was approximately $180.9 million and $156.5 million, respectively. The fair value was determined based on the closing price for the Convertible Notes on the last trading day of the reporting period and is considered as Level 2 in the fair value hierarchy.

As of the years ended December 31, 2023 and 2022, the fair value of the Pension Plan’s assets, as further described in Note 13, “Employee Benefit Plans,” to these consolidated financial statements, was approximately $3.6 million and $3.2 million, respectively. The fair value was determined by an independent actuary and is considered as Level 2 in the fair value hierarchy.

The Company monitors the availability of observable market data to assess the appropriate classification of financial instruments within the fair value hierarchy. Changes in economic conditions or model-based valuation techniques may require the transfer of financial instruments from one fair value level to another. In such instances, the transfer is reported at the beginning of the reporting period. There were no transfers between Levels 1, 2 or 3 during the years ended December 31, 2023 and 2022.

The money market account is included in cash and cash equivalents in the consolidated balance sheets as of December 31, 2023 and 2022.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Fair Value Measurements - Contractual Maturities of Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortized cost
Less than one year	$ 21,422
Total	21,422	$ 70,917
Aggregate fair value
Less than one year	21,488
Total	$ 21,488

Income Taxes - Schedule of Domestic and Foreign Components of Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
United States	$ 759	$ 30,594	$ (27,547)
International	(20,062)	(13,288)	(3,648)
(Loss) income before income taxes	$ (19,303)	$ 17,306	$ (31,195)

Financial Statement Components - Schedule of Accounts Receivable, net of Allowances (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financial Statement Components [Abstract]
Trade accounts receivable	$ 35,612	$ 40,332
Unbilled accounts receivable	43,631	33,863
Allowance for doubtful accounts and reserve for expected credit losses	(1,128)	(1,191)
Other accounts receivable	40	1,461
Total accounts receivable, net	$ 78,155	$ 74,465

Employee Benefit Plans - Schedule of Projected Benefit Obligation and Plan Assets Changes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Change in benefit obligation:
Actuarial loss (gain) on benefit obligation	$ 13	$ (418)	$ (237)
Impact of foreign currency translation	(118)	12	(1)
Change in plan assets:
Actuarial gain	(27)	0	0
Pension Plan
Change in plan assets:
Fair value of plan assets at beginning of year	3,200
Fair value of plan assets at end of year	3,600	3,200
Non-U.S. \| Pension Plan
Change in benefit obligation:
Benefit obligation at beginning of year	3,502	3,874
Service cost	264	268	396
Interest cost	146	35	21
Actuarial loss (gain) on benefit obligation	13	(418)
Benefits paid	(41)	0
Taxes, insurance premiums and administrative expenses	(61)	(50)
Impact of foreign currency translation	104	(207)
Benefit obligation at end of year	3,927	3,502	3,874
Change in plan assets:
Fair value of plan assets at beginning of year	3,181	2,958
Return on plan assets	41	26
Actuarial gain	0	72
Employer contribution	393	332
Benefits paid	(41)	0
Taxes, insurance premiums and administrative expenses	61	50
Impact of foreign currency translation	94	(157)
Fair value of plan assets at end of year	3,607	3,181	$ 2,958
Funded status, net liability	$ 320	$ 321

Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Allowance for doubtful accounts	$ 80	$ 173
Accrued liabilities	3,459	4,370
Operating lease liabilities	57,152	3,456
Deferred revenue	1,915	1,949
Stock-based compensation	3,363	3,216
Capitalized research and development expenses	40,306	20,997
Accrued lease incentive	0	2,645
Tax credits	12,994	10,948
Net operating losses	17,421	25,691
Other deferred tax assets	3,238	4,592
Gross deferred tax assets	139,928	78,037
Less: valuation allowance	(67,950)	(65,678)
Total deferred tax assets	71,978	12,359
Deferred tax liabilities:
Property, plant and equipment	24,469	4,890
Goodwill	1,416	1,272
Intangibles	39,334	41,591
Operating lease assets	39,780	3,072
Total deferred tax liabilities	104,999	50,825
Net deferred tax liability	$ (33,021)	$ (38,466)

Debt - Other Terms of the Convertible Notes (Details) - 2026 Convertible Notes	12 Months Ended
	Dec. 31, 2023 day
Debt Instrument [Line Items]
Cash redemption price (as a percent)	100.00%
Redemption period scheduled trading day before the maturity date	40 days
Conversion option 1 \| Convertible notes \| Class A voting common stock
Debt Instrument [Line Items]
Stock price trigger (as a percent)	130.00%
Trading days	20
Consecutive trading days	30

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net (loss) income	$ (16,343)	$ 19,570	$ (27,362)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-28

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482765/220-10-50-6

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-3

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-8

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-9

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-4

Reference 13: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480167/946-830-55-10

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section 45
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483581/946-220-45-7

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(9))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(1)(d))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-3

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 20: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(5))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(B))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(5))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 29: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-30

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 31: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-60B

Reference 32: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

Reference 33: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 34: http://www.xbrl.org/2003/role/disclosureRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-7

Reference 35: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 36: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1A

Reference 37: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1B

Reference 38: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 39: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

+ Details

Property, Plant and Equipment - Depreciation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Total depreciation expense	$ 24,443	$ 18,419	$ 17,523
Cost of revenue
Property, Plant and Equipment [Line Items]
Total depreciation expense	16,273	13,602	12,606
Research and development
Property, Plant and Equipment [Line Items]
Total depreciation expense	3,977	2,311	2,166
Sales and marketing
Property, Plant and Equipment [Line Items]
Total depreciation expense	2,628	1,331	1,090
General and administrative
Property, Plant and Equipment [Line Items]
Total depreciation expense	$ 1,565	$ 1,175	$ 1,661

Debt - 2028 Convertible Notes (Details)	1 Months Ended	12 Months Ended
Debt - 2028 Convertible Notes (Details)	Mar. 31, 2021 USD ($) $ / shares	Dec. 31, 2023 USD ($) $ / shares	Dec. 31, 2022 USD ($) $ / shares	Dec. 31, 2021 $ / shares	Feb. 28, 2020 $ / shares
Class A voting common stock
Debt Instrument [Line Items]
Common stock, par value (in usd per share) \| $ / shares	$ 0.001	$ 0.001	$ 0.001		$ 0.001
2028 Convertible Notes: \| Convertible notes
Debt Instrument [Line Items]
Principal amount \| $	$ 250,000,000	$ 250,000,000	$ 250,000,000
Stated rate (as a percent)	0.50%
Total net proceeds \| $	$ 217,000,000
Effective interest rate (as a percent)	0.442%
Conversion price (in usd per share) \| $ / shares	$ 179.27			$ 179.27
2028 Convertible Notes: \| Convertible notes \| Class A voting common stock
Debt Instrument [Line Items]
Conversion ratio	0.0055781	0.0055781	0.0055781

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 01, 2022
Operating Loss Carryforwards [Line Items]
Income tax (provision) benefit	$ 2,960	$ 2,264	$ 3,833
(Loss) income before income taxes	$ (19,303)	$ 17,306	$ (31,195)
Effective income tax rate (as a percent)	15.30%	(13.10%)	12.30%
Additional paid-in capital	$ 391,048	$ 364,913
Accumulated deficit	64,890	48,547
Deferred tax liability	(33,021)	(38,466)
Federal tax credits	12,800
Unrecognized tax benefits	6,170	4,800	$ 3,062
Income tax penalties and interest expense	300	$ 300
Federal Ministry of Finance, Germany
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	44,300
Tax and Customs Administration, Netherlands
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	16,300
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 63,900
Cumulative effect of adoption, adjusted balance \| Accounting Standards Update 2020-06
Operating Loss Carryforwards [Line Items]
Additional paid-in capital				$ (156,200)
Accumulated deficit				8,800
Deferred tax liability				$ 1,000

Leases - Additional Information (Details) $ in Thousands		12 Months Ended
Leases - Additional Information (Details) $ in Thousands	Aug. 01, 2023 USD ($) segment	Dec. 31, 2023 USD ($) ft²	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Lessee, Lease, Description [Line Items]
Option to extend, term (up to)		20 years
Short-term operating lease expense		$ 600	$ 600	$ 1,300
Accumulated amortization		20,300	17,700
Operating right-of-use asset, net		157,507	9,993
Total lease obligations		226,011
Lease incentive		$ 0	$ 10,468
Relay, Inc
Lessee, Lease, Description [Line Items]
Sublease area of real estate property \| ft²		17,073
Corporate Headquarters
Lessee, Lease, Description [Line Items]
Term of lease	20 years
Number of option to extend \| segment	2
Renewal term	10 years
Market rental rate (as a percent)	100.00%
Operating right-of-use asset, net	$ 156,000
Total lease obligations	223,100
Lease incentive	67,800
Security deposit	2,500
Escrow to fund	$ 1,000

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2023
Auditor Information [Abstract]
Auditor Name	Ernst & Young LLP
Auditor Location	Raleigh, NC
Auditor Firm ID	42

Goodwill and Intangible Assets - Summary of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Accumulated Amortization	$ (63,666)	$ (44,637)
Net Carrying Value	166,290
Gross Amount	230,580	222,007
Net Carrying Value	166,914	177,370
Licenses, indefinite lived
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Licenses, indefinite lived	624	624
Customer relationships
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Gross Amount	147,426	141,146
Accumulated Amortization	(35,599)	(25,037)
Net Carrying Value	$ 111,827	$ 116,109
Customer relationships \| Minimum
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Amortization Period	15 years	15 years
Customer relationships \| Maximum
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Amortization Period	20 years	20 years
Developed technology
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Gross Amount	$ 79,702	$ 77,409
Accumulated Amortization	(25,239)	(16,772)
Net Carrying Value	$ 54,463	$ 60,637
Amortization Period	10 years	10 years
Other, definite lived
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Gross Amount	$ 2,828	$ 2,828
Accumulated Amortization	(2,828)	(2,828)
Net Carrying Value	$ 0	$ 0
Other, definite lived \| Minimum
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Amortization Period	2 years	2 years
Other, definite lived \| Maximum
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Amortization Period	7 years	7 years

Summary of Significant Accounting Policies - Revenue By Category (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenue from External Customer [Line Items]
Revenue	$ 601,117	$ 573,152	$ 490,907
Cloud communications
Revenue from External Customer [Line Items]
Revenue	478,892	474,576	449,656
Messaging surcharges
Revenue from External Customer [Line Items]
Revenue	$ 122,225	$ 98,576	$ 41,251

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479941/924-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-30

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-40

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-41

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-4

+ Details

Commitments and Contingencies - Additional Information (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Lessee, Lease, Description [Line Items]
Lease payments of initial term	$ 490,704
Non-cancellable purchase obligation	23,000
Non-cancellable purchase obligation, fulfilled within a year	12,900
Office Space
Lessee, Lease, Description [Line Items]
Lease payments of initial term	$ 496,100

Leases - Supplemental Cash Flow and Other Information (Details)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Weighted average remaining lease term (in years)	19 years 3 months 18 days	2 years 1 month 13 days	2 years 11 months 12 days
Weighted average discount rate	8.76%	4.58%	4.78%

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Schedule of Stock Option Activity

The following summarizes the stock option activity for the year ended December 31, 2023:


	Number of options outstanding	Weighted- average exercise price (Per share)		Weighted- average remaining contract life (In years)	Aggregate intrinsic value (In thousands)
Outstanding as of December 31, 2022	159,741	$	10.42	2.57	$	2,001
Granted	—	—
Exercised	(61,349)	6.74
Forfeited or expired	(912)	9.46
Outstanding as of December 31, 2023	97,480	$	12.75	2.97	$	332

Options vested and exercisable at December 31, 2023	97,480	$	12.75	2.97	$	332
Options vested and expected to vest as of December 31, 2023	97,480	$	12.75	2.97	$	332

Schedule of Restricted Stock Unit Activity

The following summarizes the RSU activity for the year ended December 31, 2023:


	Number of awards outstanding	Weighted-average grant date fair value (Per share)
Nonvested RSUs as of December 31, 2022	2,607,106	$	32.33
Granted	3,431,074	11.35
Vested	(804,962)	31.29
Forfeited	(167,059)	28.77
Nonvested RSUs as of December 31, 2023	5,066,159	$	18.41


	Year ended December 31,
		2023		2022		2021

Weighted average grant date fair value of RSUs granted (per share)		$	11.35	$	30.43	$	143.31
Total fair value of RSUs vested (in thousands)		25,186		15,038		12,571

Schedule of Stock-Based Compensation Expense

The Company recognized total stock-based compensation expense as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
Cost of revenue		$	1,136	$	404	$	364
Research and development		15,661		7,523		3,681
Sales and marketing		6,273		2,808		2,225
General and administrative		13,922		9,920		8,267
Total		$	36,992	$	20,655	$	14,537

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Maturities of marketable securities	$ 91,800	$ 74,300	$ 0
Proceeds from sale of marketable securities	38,300	34,400	0
Interest earned on marketable securities (less than)	2,000	1,200	$ 0
Accrued interest, after allowance for credit loss	$ 300	$ 300
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Prepaid expenses and other current assets	Prepaid expenses and other current assets
Pension Plan
Debt Instrument [Line Items]
Fair value of plan assets	$ 3,600	$ 3,200
Convertible notes \| 2026 Convertible Notes:
Debt Instrument [Line Items]
Fair value	145,500	180,900
Convertible notes \| 2028 Convertible Notes:
Debt Instrument [Line Items]
Fair value	$ 157,600	$ 156,500

Consolidated Statements of Changes in Stockholders’ Equity - USD ($) $ in Thousands	Total	Adjustment to opening retained earnings due to adoption of ASU 2020-06	Class A voting common stock	Class B voting common stock	Common stock Class A voting common stock	Common stock Class B voting common stock	Additional paid-in capital	Additional paid-in capital Adjustment to opening retained earnings due to adoption of ASU 2020-06	Accumulated other comprehensive income (loss)	Accumulated deficit	Accumulated deficit Adjustment to opening retained earnings due to adoption of ASU 2020-06
Beginning balance (in shares) at Dec. 31, 2020					22,413,004	2,496,125
Beginning balance at Dec. 31, 2020	$ 429,923				$ 22	$ 2	$ 451,463		$ 27,941	$ (49,505)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of debt conversion option	66,908						66,908
Debt conversion option issuance costs, net of tax	(2,019)						(2,019)
Capped call option purchase price	(25,500)						(25,500)
Exercises of vested stock options (in shares)					73,985
Exercises of vested stock options	923						923
Vesting of restricted stock units (in shares)					186,502
Equity awards withheld for tax liability (in shares)					(26,458)
Equity awards withheld for tax liability	(3,835)						(3,835)
Conversion of Class B voting common stock to Class A voting common stock (in shares)					530,955	(530,955)
Conversion of Class B voting common stock to Class A voting common stock	1				$ 1	$ 0
Foreign currency translation	(41,150)								(41,150)
Unrealized gain/loss on employee benefit pension plan	169								169
Stock-based compensation	14,537						14,537
Net income (loss)	(27,362)									(27,362)
Ending balance (in shares) at Dec. 31, 2021					23,177,988	1,965,170
Ending balance at Dec. 31, 2021	$ 412,595				$ 23	$ 2	502,477		(13,040)	(76,867)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update	Accounting Standards Update 2020-06
Exercises of vested stock options (in shares)					20,468
Exercises of vested stock options	$ 163						163
Vesting of restricted stock units (in shares)					231,234
Equity awards withheld for tax liability (in shares)					(50,690)
Equity awards withheld for tax liability	(2,134)						(2,134)
Unrealized loss on marketable securities	314								314
Foreign currency translation	(31,855)								(31,855)
Unrealized gain/loss on employee benefit pension plan	367								367
Stock-based compensation	20,655						20,655
Net income (loss)	19,570									19,570
Ending balance (in shares) at Dec. 31, 2022			23,379,000	1,965,170	23,379,000	1,965,170
Ending balance at Dec. 31, 2022	$ 272,177	$ (147,498)			$ 23	$ 2	364,913	$ (156,248)	(44,214)	(48,547)	$ 8,750
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercises of vested stock options (in shares)	61,349				61,349
Exercises of vested stock options	$ 414						414
Vesting of restricted stock units (in shares)					804,962
Vesting of restricted stock units	1				$ 1
Equity awards withheld for tax liability (in shares)					(46,313)
Equity awards withheld for tax liability	(941)						(941)
Conversion of Class B voting common stock to Class A voting common stock (in shares)					7,142	(7,142)
Conversion of Class B voting common stock to Class A voting common stock	0
Unrealized loss on marketable securities	(248)								(248)
Foreign currency translation	15,698								15,698
Unrealized gain/loss on employee benefit pension plan	(30)								(30)
Stock-based compensation	26,662						26,662
Net income (loss)	(16,343)									(16,343)
Ending balance (in shares) at Dec. 31, 2023			24,206,140	1,958,028	24,206,140	1,958,028
Ending balance at Dec. 31, 2023	$ 297,390				$ 24	$ 2	$ 391,048		$ (28,794)	$ (64,890)

Summary of Significant Accounting Policies - Recently Adopted Accounting Standards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Jan. 01, 2022
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit	$ 64,890	$ 48,547
Additional paid-in capital	(391,048)	(364,913)
Deferred tax liability	(33,021)	(38,466)
Convertible senior notes	418,526	480,546
Interest expense, debt	3,719	5,224
Accounting Standards Update 2020-06 \| Cumulative effect of adoption, adjusted balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit			$ 8,800
Additional paid-in capital			156,200
Deferred tax liability			1,000
Convertible senior notes			$ 148,400
Interest expense, debt	$ 29,200	$ 27,200

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 50
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147477123/405-50-65-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 13
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482477/820-10-65-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482477/820-10-65-13

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-5

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-5

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 5
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-5

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 5
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-5

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (h)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (h)(1)(iii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (h)(1)(iv)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (i)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (i)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480528/815-20-65-6

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 832
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483482/832-10-65-1

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 832
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483482/832-10-65-1

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479845/805-20-65-3

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479845/805-20-65-3

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479845/805-20-65-3

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479832/842-10-65-5

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479832/842-10-65-5

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 5
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479832/842-10-65-5

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 5
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479832/842-10-65-5

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-2

Reference 29: http://www.xbrl.org/2003/role/disclosureRef
-Topic 848
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483550/848-10-65-2

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 848
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483550/848-10-65-2

Reference 31: http://www.xbrl.org/2003/role/disclosureRef
-Topic 848
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483550/848-10-65-2

Reference 32: http://www.xbrl.org/2003/role/disclosureRef
-Topic 848
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)(3)(iii)(01)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483550/848-10-65-2

Reference 33: http://www.xbrl.org/2003/role/disclosureRef
-Topic 848
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)(3)(iii)(03)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483550/848-10-65-2

Reference 34: http://www.xbrl.org/2003/role/disclosureRef
-Topic 105
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479343/105-10-65-6

Reference 35: http://www.xbrl.org/2003/role/disclosureRef
-Topic 105
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479343/105-10-65-6

Reference 36: http://www.xbrl.org/2003/role/disclosureRef
-Topic 105
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479343/105-10-65-6

Reference 37: http://www.xbrl.org/2003/role/disclosureRef
-Topic 105
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479343/105-10-65-6

Reference 38: http://www.xbrl.org/2003/role/disclosureRef
-Topic 105
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479343/105-10-65-6

Reference 39: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 40: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 41: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 42: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (f)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 43: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (f)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 44: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 45: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 46: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 47: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 48: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(2)(iv)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 49: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (h)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 50: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (h)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480016/944-40-65-2

Reference 51: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 11.M.Q2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480530/250-10-S99-5

Reference 52: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-4

Reference 53: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-4

Reference 54: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-4

Reference 55: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 8
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482615/740-10-65-8

Reference 56: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482615/740-10-65-8

Reference 57: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 8
-Subparagraph (d)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482615/740-10-65-8

Reference 58: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 8
-Subparagraph (d)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482615/740-10-65-8

Reference 59: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 4
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-4

Reference 60: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 4
-Subparagraph (e)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-4

Reference 61: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 4
-Subparagraph (e)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479654/326-10-65-4

Reference 62: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 15
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480336/718-10-65-15

Reference 63: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 15
-Subparagraph (f)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480336/718-10-65-15

Reference 64: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 15
-Subparagraph (f)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480336/718-10-65-15

Reference 65: http://www.xbrl.org/2003/role/disclosureRef
-Topic 926
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483194/926-20-65-2

Reference 66: http://www.xbrl.org/2003/role/disclosureRef
-Topic 926
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483194/926-20-65-2

Reference 67: http://www.xbrl.org/2003/role/disclosureRef
-Topic 926
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483194/926-20-65-2

Reference 68: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-3

Reference 69: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-1

Reference 70: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-1

Reference 71: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-1

Reference 72: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-1

Reference 73: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482635/260-10-55-15

Reference 74: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483421/250-10-45-6

Reference 75: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482833/825-10-65-6

Reference 76: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482833/825-10-65-6

Reference 77: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482833/825-10-65-6

Reference 78: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 65
-Paragraph 6
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482833/825-10-65-6

Reference 79: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 80: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 81: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 82: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 83: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 84: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 85: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 86: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (e)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 87: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (e)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 88: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (e)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 89: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 90: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481925/310-20-65-2

Reference 91: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481925/310-20-65-2

Reference 92: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480424/946-10-50-3

+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Basis of Presentation

The consolidated financial statements and accompanying notes were prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”).

Reclassification

The Company reclassified certain prior year amounts to conform to the current year presentation. These reclassifications had no impact on the previously reported total assets, liabilities, stockholder’s deficit or net income.

Principles of Consolidation

The consolidated financial statements include the accounts of Bandwidth Inc. and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of the Company’s consolidated financial statements in conformity with GAAP requires the Company to make estimates and judgments that affect the amounts reported in these financial statements and accompanying notes. These estimates in the consolidated financial statements include, but are not limited to, allowance for doubtful accounts, reserve for expected credit losses, reserve for sales credits, recoverability of long lived and intangible assets, fair value of acquired intangible assets and goodwill, discount rates used in the valuation of right-of-use assets and lease liabilities, the fair value of the liability components of the Company’s Convertible Notes (as defined herein), estimated period of benefit, valuation allowances on deferred tax assets, certain accrued expenses and contingencies, economic and demographic actuarial assumptions related to pension and other postretirement benefit costs and liabilities. Although the Company believes that the estimates it uses are reasonable, due to the inherent uncertainty involved in making these estimates, actual results reported in future periods could differ from those estimates.

Revenue Recognition

Revenue recognition commences upon transfer of control of promised goods or services to customers in an amount that the Company expects to receive in exchange for those products or services.

The Company determines revenue recognition through the following steps:

•identification of the contract, or contracts, with a customer;

•identification of the performance obligations in the contract;

•determination of the transaction price;

•allocation of the transaction price to the performance obligations in the contract; and

•recognition of revenue, when, or as, the Company satisfies a performance obligation.

Infrequently, Bandwidth’s contracts with customers may include multiple performance obligations. For such arrangements, revenues are allocated to each performance obligation based on its relative standalone selling price. Generally, standalone selling prices are determined based on the prices charged to similar customers for similar services.

When required as part of providing service, revenues and associated expenses related to nonrefundable, upfront service activation and setup fees are deferred and recognized over the longer of the associated service contract period or estimated customer life.

The Company’s contracts do not contain general rights of return. However, occasionally credits may be issued. The Company’s contracts do not provide customers with the right to take possession of the software supporting the applications. Amounts that have been invoiced are recorded in accounts receivable and in revenue or deferred revenue depending on whether the revenue recognition criteria have been met.

The Company maintains a reserve for sales credits. Credits are accounted for as variable consideration and are estimated based on several inputs including historical experience and current trends of credit issuances. Adjustments to the reserve are recorded against revenue.

The Company has various sales commission plans for which eligible employees can earn commissions from the sale of products and services to customers. Eligible employees must be employed at the time of payment in order to receive a commission. The Company pays commissions over time and a corresponding requisite substantive service condition exists for the employee to receive the commission. The Company determined that the timing of the commission payments and the underlying service performed by the employee were commensurate. Accordingly, sales commissions are generally expensed as incurred. These costs are recorded within sales and marketing expenses.

Nature of Products and Services

Revenue consists primarily of two categories: (1) cloud communications and (2) messaging surcharges, which are described and quantified below.


	Year ended December 31,
	2023		2022		2021

	(In thousands)

Cloud communications	$	478,892	$	474,576	$	449,656
Messaging surcharges	122,225		98,576		41,251
Total revenue	$	601,117	$	573,152	$	490,907

Cloud Communications

Cloud communications revenue consists of the sale of communications services offered through Application Programming Interface (“API”) software solutions to customers and is derived from (i) reoccurring sources such as per minute voice usage and voice calling, per text message usage and other usage services and fees, and (ii) monthly recurring charges arising from phone number services, 911-enabled phone number services, messaging services and other services.

The majority of the Company’s cloud communications revenue is generated from reoccurring fees earned from customers accessing and using the Company’s communications platform. Access to the Company’s communications platform is considered a series of distinct services with continuous transfer of control to the customer, comprising one performance obligation. Reoccurring fees are recognized in revenue in the period the

traffic traverses the Company’s network. For the years ended December 31, 2023, 2022 and 2021, the revenue from reoccurring cloud communications fees represented $346.9 million, $354.0 million, and $355.3 million of total revenue, respectively.

Revenue from recurring fees is recognized on a ratable basis as the service is provided, which is typically one month. For the years ended December 31, 2023, 2022 and 2021, the revenue from recurring cloud communications fees represented $132.0 million, $120.6 million and $94.4 million of total revenue, respectively.

Messaging surcharges

Messaging surcharge revenue consists of pass-through messaging surcharges imposed by the major mobile carriers in North America and is recognized in revenue during the period in which the messaging traffic traverses the Company’s network.

Contract Assets and Liabilities

The following table provides information about receivables and contract liabilities from contracts with customers:


	As of December 31,
	2023		2022

	(In thousands)
Receivables (1)	$	78,155	$	74,465
Contract liabilities (2)	16,465		15,487

________________________

(1) Included in accounts receivable, net of allowance for doubtful accounts on the consolidated balance sheets.

(2) Included in current portion of deferred revenue and deferred revenue, net of current portion on the consolidated balance sheets.

Deferred revenue is recorded when cash payments are received in advance of future usage on contracts. Revenue is typically recognized in the following month when service is rendered or, in the case of nonrefundable upfront fees, over the estimated period of benefit from the date the fee is incurred by the customer. Customer refundable payments are recorded as advanced billings. During the year ended December 31, 2023, the Company recognized revenue of $5.8 million related to contract liabilities recorded at the beginning of the year. The Company expects to recognize $8.1 million in revenue over the next 12 months related to its contract liabilities as of December 31, 2023.

Cost of Revenue

Cost of revenue consists of fees paid to other network service providers, network operations costs, personnel costs, allocated costs of facilities and information technology, amortization of acquired technology intangibles and depreciation.

Fees paid to other network service providers arise when the Company purchases services such as minutes of use, phone numbers, messages, porting of customer numbers and network circuits.

Network operations costs are incurred for web services and cloud infrastructure, capacity planning and management, software licenses, hardware and software maintenance fees, customer support and network-related facility rents.

Personnel costs (including non-cash stock-based compensation expenses) arise for employees who are responsible for the delivery of services, and operations and maintenance of, the communications network.

Research and Development

Research and development expenses consist of salaries and related personnel costs for the design, development, testing and enhancement of our cloud network and software products. Research and development expenses include depreciation and allocated costs for facilities and information technology utilized by our research and development staff.

Sales and Marketing, General and Administrative

Sales and Marketing

Sales and marketing expenses consist of salaries and related personnel costs, commissions, and costs related to advertising, marketing, brand awareness activities, sales support and professional services fees, and customer billing and collections functions. Sales and marketing expenses include depreciation, amortization of acquired customer relationship intangible assets, and allocated costs of facilities and information technology utilized by our sales and marketing staff.

General and Administrative

General and administrative expenses consist of salaries and related personnel costs for accounting, legal, human resources, corporate, and other administrative and compliance functions. General and administrative expenses include depreciation, expenditures for third party professional services, and allocated costs of facilities and information technology utilized by our corporate and administrative staff.

Cash and Cash Equivalents

The Company classifies all highly liquid investments with original stated maturities of three months or less from the date of purchase as cash equivalents. All highly liquid investments with original stated maturities of greater than three months from the date of purchase are classified as current marketable securities. Cash deposits are primarily in financial institutions in the United States. However, cash for monthly operating costs of international operations are deposited in banks outside the United States. The Company has a policy of making investments only with commercial institutions that have at least an investment grade credit rating. The Company utilizes money market funds as an investment option and only invests in AAA rated funds.

Marketable Securities

The Company’s marketable securities consist of time deposits, U.S. treasury debt securities, commercial paper, and corporate debt securities. The Company classifies marketable securities as available-for-sale at the time of purchase and reevaluates such classification as of each balance sheet date. The Company may sell these securities at any time for use in current operations even if they have not yet reached maturity. As a result, the Company classifies investments with maturities greater than 90 days as marketable securities in the accompanying consolidated balance sheets. Available-for-sale securities are recorded at fair value at the end of each reporting period. Unrealized gains and losses are excluded from earnings and recorded as a separate component within accumulated other comprehensive loss on the consolidated balance sheets until realized. Interest income is reported within other income (expense), net on the consolidated statements of operations. The Company evaluates its investments to assess whether the amortized cost basis is in excess of estimated fair value and determines what amount of that difference, if any, is caused by expected credit losses. Allowance for credit losses are recognized as a charge in other income (expense), net on the consolidated statements of operations, and any remaining unrealized losses are included in accumulated other comprehensive loss on the consolidated balance sheets. Due to the nature and investment grade of the Company’s marketable securities, there were no credit losses recorded for the year ended December 31, 2023. There have been no impairment charges for any unrealized losses during the period. The Company determines realized gains and losses on the sale of marketable securities using the specific identification

method and records such gains and losses in other income (expense), net on the consolidated statements of operations.

Accounts Receivable and Current Expected Credit Losses

Accounts receivable are stated at realizable value, net of allowances, which includes an allowance for doubtful accounts and a reserve for expected credit losses. The allowance for doubtful accounts is based on management’s assessment of the collectability of its customer accounts. The Company regularly reviews the composition of the accounts receivable aging, historical bad debts, changes in payment patterns, customer creditworthiness, current economic trends, and reasonable and supportable forecasts about the future. Relevant risk characteristics include customer size and historical loss patterns. Management has evaluated the expected credit losses related to trade accounts receivable and determined that allowances of approximately $1.1 million and $1.2 million for uncollectible accounts and customer balances that are disputed were required as of December 31, 2023 and 2022, respectively. Refer to Note 4, “Financial Statement Components” to these consolidated financial statements, for a rollforward of the components of the allowances as of December 31, 2023 and 2022.

The Company includes unbilled receivables in its accounts receivable balance. Generally, these receivables represent earned revenue from services provided to customers, which will be billed in the next billing cycle. All amounts are considered collectible and billable.

Property, Plant and Equipment, net

Deferred Costs

The Company defers certain direct and incremental upfront costs related to the generation of a revenue stream or obtaining a new customer agreement. These costs include installment fees, activation and other telecommunication fees. The Company capitalizes these costs and amortizes them over the longer of the term of the customer contract or the estimated period of benefit, which is approximately four years.

Internal-Use Software Development Costs

Internal-use software includes software that has been acquired, internally developed, or modified exclusively to meet the Company’s needs. The Company capitalizes qualifying internal-use software development costs that are incurred during the application development stage. Capitalization of costs begins when two criteria are

met: (i) the preliminary project stage is completed, and (ii) it is probable that the software will be completed and used for its intended function. Capitalization ceases when the software is substantially complete and ready for its intended use, including the completion of all significant testing. The Company also capitalizes costs related to specific upgrades and enhancements when the expenditures will result in additional functionality, and expenses costs incurred for maintenance and minor upgrades and enhancements. Costs related to preliminary project activities and post-implementation operating activities are expensed as incurred.

Capitalized costs of platform and other software applications are included in property, plant and equipment, net. These assets are placed into service when ready for use and amortized over the estimated useful life of the software on a straight-line basis over four years. Management evaluates the useful life of these assets on an annual basis and tests for impairment whenever events or changes in circumstances occur that could impact the recoverability of these assets.

Concentration of Credit Risk

Financial instruments that are exposed to concentration of credit risk consist primarily of cash and cash equivalents, marketable securities and trade accounts receivable. The Company maintains its cash, cash equivalents and marketable securities with high credit-quality financial institutions. Certain balances held by such financial institutions exceed federally-insured limits.

Debt Issuance Costs

The Company incurs debt issuance costs associated with obtaining and entering into credit agreements and issuing convertible notes. These costs customarily include non-refundable structuring fees, commitment fees, up-front fees and syndication expenses. The Company has a policy of deferring and amortizing these costs based on the effective interest method over the term of the credit agreements or the convertible notes, as applicable.

Amortization of Intangibles

Intangible assets with determinable economic lives are carried at cost, less accumulated amortization. Amortization is computed over the estimated useful life of each asset on a straight-line basis. The Company determines the useful lives of identifiable intangible assets after considering the specific facts and circumstances related to each intangible asset. Factors the Company considers when determining useful lives include the contractual term of any agreement related to the asset, the historical performance of the asset, the Company’s long-term strategy for using the asset, any laws or other local regulations which could impact the useful life of the asset and other economic factors, including competition and specific market conditions. Intangible assets without determinable economic lives are carried at historical cost and reviewed for impairment at least annually.

Goodwill

In accordance with Accounting Standards Codification 350, “Intangibles - Goodwill and Other” (“ASC 350”), goodwill is not amortized, but rather is reviewed for impairment at the reporting unit level on the last day of the Company’s fourth quarter of each fiscal year, or when there is evidence that events or changes in circumstances indicate that the fair value of the reporting unit is less than the carrying amount of the reporting unit, including goodwill.

The Company establishes its reporting units based on its current organizational structure and management’s view of the business. The Company has determined it has one reporting unit.

Under ASC 350, the Company has the option to first assess qualitatively whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount, including goodwill. In performing qualitative assessments, consistent with ASC 350-20-35-3C, the Company considers, among other factors, macroeconomic conditions (both in the United States and internationally), the Company’s overall financial performance (including, but not limited to, comparisons to prior periods, current period internal expectations, and comparable peer companies), broader industry and market considerations, and the trading price performance of the Company’s Class A common stock.

As of December 31, 2023, the Company completed a quantitative assessment under ASC 350 and determined that there was not an impairment of goodwill.

The estimated fair value of the Company’s one reporting unit was based on the income approach and the market approach. Significant assumptions used within the discounted cash flow method under the income approach included estimated revenue projections and a risk adjusted discount rate. Significant assumptions used with the market approach included estimated revenue projections and an appropriate risk adjusted earnings multiple.

Impairment of Long-Lived Assets

The Company evaluates long-lived assets, including property, plant and equipment and definite lived intangible assets, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets held and used is measured by a comparison of the carrying amount of an asset or an asset group to estimated undiscounted future net cash flows expected to be generated by the asset or asset group. If such evaluation indicates that the carrying amount of the asset or the asset group is not recoverable, any impairment loss would be equal to the amount the carrying value exceeds the fair value.

Business Combinations

The Company uses the acquisition method of accounting for business combinations which requires the tangible and intangible assets acquired and liabilities assumed to be recorded at their respective fair market value as of the acquisition date. Goodwill represents the excess of the consideration transferred over the fair value of the net assets acquired. The fair values of the assets acquired and liabilities assumed are determined based upon the Company’s valuation and involves making significant estimates and assumptions based on facts and circumstances that existed as of the acquisition date. The Company uses a measurement period following the acquisition date to gather information that existed as of the acquisition date that is needed to determine the fair value of the assets acquired and liabilities assumed. The measurement period ends once all information is obtained, but no later than one year from the acquisition date.

Advertising Costs

The Company expenses advertising costs as incurred.

Commissions

Commissions consist of variable compensation earned by sales personnel and third-party resellers. Sales commissions associated with the acquisition of a new customer contract are paid over time, based on monthly revenues, and are recognized as sales and marketing expense in the period incurred.

Share-Based Compensation

Stock-Based Compensation

The Company accounts for stock-based compensation expense related to all stock-based awards based on the fair value of the award on the grant date. Stock-based compensation expense is recognized on a straight-line basis over the requisite service period, which is generally three or four years for stock options and restricted stock units granted to employees, and one year for restricted stock units granted to non-employee members of the Board of Directors. The fair value of the restricted stock units is determined using the fair value of the Company’s Class A common stock on the date of grant. The Company uses the Black-Scholes option pricing model, net of estimated forfeitures, to measure the fair value of its stock options.

The Company has elected to estimate expected forfeitures, and, as such, the Company must also determine a forfeiture rate to calculate the stock-based compensation expense for awards. Through December 31, 2023, the Company recognized compensation expense for only the portion of restricted stock units expected to vest using an estimated forfeiture rate that was derived from historical employee termination behavior. As of December 31, 2023, all outstanding stock options are fully vested.

Income Taxes

The Company accounts for income taxes under the asset and liability method. Under this method, deferred tax assets and liabilities are determined based on temporary differences between the financial statement and tax basis of assets and liabilities using enacted tax rates. The Company recognizes the effect of a change in tax rates on deferred tax assets and liabilities in the period that includes the enactment date.

The Company reduces the measurement of a deferred tax asset, if necessary, by a valuation allowance if it is more likely than not that it will not realize some or all the deferred tax asset. Quarterly, the Company reviews the deferred tax assets for recoverability based on historical taxable income, projected future taxable income, the expected timing of the reversals of existing temporary differences and the implementation of prudent and feasible tax planning strategies. The evaluation of the recoverability of deferred tax assets requires judgment in assessing future profitability. Should there be a change in the ability to recover deferred tax assets, the Company’s income tax provision would increase or decrease in the period in which the assessment is changed.

The Company accounts for uncertain tax positions by recognizing the financial statement effects of a tax position only when, based upon technical merits, it is more likely than not that the position will be sustained upon examination. The tax benefit recognized is measured as the largest amount of benefit determined on a cumulative probability basis that the Company believes is more likely than not to be realized upon ultimate settlement of the position. The Company recognizes potential accrued interest and penalties associated with unrecognized tax positions in income tax expense.

Operating Segments

Operating segments are defined as components of an enterprise for which separate financial information is available and evaluated regularly by the chief operating decision maker in deciding how to make operating decisions, allocate resources and in assessing performance. The Company’s chief operating decision maker is its Chief Executive Officer, who evaluates the Company’s financial information on a consolidated basis. Accordingly, the Company has determined that it operates in one operating segment.

Earnings per Share

Basic earnings per share attributable to common stockholders is calculated by dividing the net (loss) income attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period.

Diluted net income per share is calculated by giving effect to all potentially dilutive common stock when determining the weighted-average number of common shares outstanding. For purposes of the diluted net (loss) income per share calculation, options to purchase common stock, restricted stock units and redeemable convertible preferred stock are considered to be potential common stock.

Foreign currency translation

The Company has foreign operations with non-USD functional currencies. The Euro and British Pound are the primary functional currencies for the Company’s international operations.

All of the assets and liabilities of these subsidiaries are translated to U.S. dollars at the exchange rate in effect at the balance sheet date, and equity accounts are translated at historical exchange rates. Revenue and expenses are translated at average exchange rates in effect during each reporting period. The net effect of currency translation adjustments is included in shareholder’s equity as a component of accumulated other comprehensive loss in the accompanying consolidated balance sheets.

Foreign currency transaction gains and losses are realized upon cash settlement of transactions denominated in currencies others than the functional currency. They result from exchange rate changes during the period of time between the consummation and cash settlement of such transactions. When realized, foreign currency transaction

gains and losses are recognized in current period earnings as incurred, and included in other income (expense), net in the Company’s consolidated statements of operations.

Foreign exchange gains and losses, which result from the process of remeasuring foreign currency assets and liabilities into the appropriate functional currency at exchange rates in place as of the reporting date, are included in other income (expense), net in the Company’s consolidated statements of operations.

Fair Value of Financial Instruments

The Company minimizes its credit risk associated with investments by investing primarily in investment grade, liquid securities. The Company policy is designed to preserve capital, maintain liquidity and minimize credit risk, and the policy limits exposure to any one issuer and also establishes minimum credit ratings of approved investments. Periodic evaluations of relative credit standing of those issuers are considered in the Company's investment strategy.

The Company uses a three-tier fair value hierarchy to classify and disclose all assets and liabilities measured at fair value on a recurring basis, as well as assets and liabilities measured at fair value on a non-recurring basis, in periods subsequent to their initial measurement. The hierarchy requires use of observable inputs when available, and to minimize the use of unobservable inputs when determining fair value. The three tiers are defined as follows:

•Level 1. Observable inputs based on unadjusted quoted prices in active markets for identical assets or liabilities;

•Level 2. Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and

•Level 3. Unobservable inputs for which there is little or no market data, which requires the Company to develop its own assumptions.

A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

Comprehensive Loss

The Company has elected to present comprehensive loss and its components as a separate financial statement. Comprehensive income refers to net income and other revenue, expenses, gains and losses that, under generally accepted accounting principles, are recorded as an element of stockholders’ equity but are excluded from the calculation of net income.

Recent Accounting Pronouncements Not Yet Adopted

In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (“ASU 2023-07”), which requires public entities to disclose information about their reportable segments’ significant expenses on an interim and annual basis. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The Company is evaluating the effect of adopting this new accounting guidance on its financial statements, but does not intend to early adopt.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). The amendments in this update require that public business entities on an annual basis (1) disclose specific categories in the rate reconciliation and (2) provide additional information for reconciling items that meet a quantitative threshold (if the effect of those reconciling items is equal to or greater than 5 percent of the amount computed by multiplying pretax income [or loss] by the applicable statutory income tax rate). The amendments also require entities on an annual basis to disclose disaggregated amounts of income taxes paid. ASU 2023-09 is effective for annual periods beginning after December 15, 2024. Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. The Company is evaluating the effect of adopting this new accounting guidance on its financial statements, but does not intend to early adopt.

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities
Net (loss) income	$ (16,343)	$ 19,570	$ (27,362)
Adjustments to reconcile net (loss) income to net cash provided by operating activities
Depreciation and amortization	41,717	35,599	36,642
Non-cash reduction to the right-of-use asset	9,323	6,977	5,722
Amortization of debt discount and issuance costs	2,520	3,082	26,754
Stock-based compensation	36,992	20,655	14,537
Deferred taxes and other	(5,942)	(5,557)	(7,486)
Net gain on extinguishment of debt	(12,767)	(40,205)	0
Changes in operating assets and liabilities:
Accounts receivable, net of allowances	(3,454)	(13,341)	(6,711)
Prepaid expenses and other assets	2,141	(5,795)	(6,751)
Accounts payable	5,385	17,210	1,992
Accrued expenses and other liabilities	(10,592)	4,291	9,693
Operating right-of-use liability	(9,979)	(7,580)	(6,227)
Net cash provided by operating activities	39,001	34,906	40,803
Cash flows from investing activities
Purchase of property, plant and equipment	(9,257)	(41,661)	(17,686)
Deposits for construction in progress	0	(18,674)	(3,000)
Capitalized software development costs	(10,642)	(3,755)	(3,926)
Purchase of land	0	0	(30,017)
Proceeds from sale of land	0	0	17,462
Purchase of marketable securities	(80,625)	(179,598)	0
Proceeds from sales and maturities of marketable securities	130,120	108,681	0
Proceeds from sales and maturities of other investments	0	0	40,000
Proceeds from sale of business	1,253	1,558	0
Net cash provided by (used in) investing activities	30,849	(133,449)	2,833
Cash flows from financing activities
Payments on finance leases	(157)	(190)	(212)
Proceeds from issuance of convertible senior notes	0	0	250,000
Net cash paid for debt extinguishment	(51,259)	(117,286)	0
Purchase of Capped Call	0	0	(25,500)
Payment of Acquisition holdback	0	0	(6,689)
Payment of debt issuance costs	(710)	(553)	(7,544)
Proceeds from exercises of stock options	413	163	926
Value of equity awards withheld for tax liabilities	(1,062)	(2,139)	(3,954)
Net cash used in financing activities	(52,775)	(120,005)	207,027
Effect of exchange rate changes on cash, cash equivalents and restricted cash	610	881	189
Net increase (decrease) in cash, cash equivalents, and restricted cash	17,685	(217,667)	250,852
Cash, cash equivalents, and restricted cash, beginning of period	114,622	332,289	81,437
Cash, cash equivalents, and restricted cash, end of period	132,307	114,622	332,289
Reconciliation of cash, cash equivalents, and restricted cash, end of period
Cash and cash equivalents	131,987	113,641	331,453
Restricted cash included in prepaid expenses and other current assets	320	981	836
Total cash, cash equivalents, and restricted cash, end of period	132,307	114,622	332,289
Supplemental disclosure of cash flow information
Cash (received from) paid for interest	(1,500)	18	1,476
Cash paid for taxes, net	7,203	3,932	1,999
Right-of-use assets obtained in exchange for new operating lease liabilities	156,025	3,421	526
Supplemental disclosure of noncash investing and financing activities
Purchase of property, plant and equipment, accrued but not paid	6,871	1,741	3,760
Purchase of property and equipment through lease incentive	57,329	5,791	4,677
Purchase of property and equipment through use of escrow deposits	$ 20,674	$ 0	$ 0

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022	Mar. 31, 2021	Feb. 28, 2020
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Class A voting common stock
Common stock, par value (in usd per share)	$ 0.001	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	24,206,140	23,379,000
Common stock, shares outstanding (in shares)	24,206,140	23,379,000
Class B voting common stock
Common stock, par value (in usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares issued (in shares)	1,958,028	1,965,170
Common stock, shares outstanding (in shares)	1,958,028	1,965,170

Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 36,992	$ 20,655	$ 14,537
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	1,136	404	364
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	15,661	7,523	3,681
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	6,273	2,808	2,225
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 13,922	$ 9,920	$ 8,267

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Schedule of Assets Measured at Fair Value on a Recurring Basis

The following tables summarize the Company’s financial assets measured at fair value as of December 31, 2023 and 2022:


	Amortized cost or carrying value		Unrealized gains		Unrealized losses		Fair value measurements on a recurring basis December 31, 2023
							Level 1		Level 2		Level 3		Total

	(In thousands)
Financial assets:
Cash and cash equivalents:
Money market account	$	120,724	$	—	$	—	$	120,724	$	—	$	—	$	120,724







Total included in cash and cash equivalents	120,724		—		—		120,724		—		—		120,724
Marketable securities:
Time deposits	20,000		—		—		20,000		—		—		20,000


Commercial paper	1,422		66		—		1,488		—		—		1,488
Total marketable securities	21,422		66		—		21,488		—		—		21,488



Total financial assets	$	142,146	$	66	$	—	$	142,212	$	—	$	—	$	142,212


	Amortized cost or carrying value		Unrealized gains		Unrealized losses		Fair value measurements on a recurring basis December 31, 2022
							Level 1		Level 2		Level 3		Total

	(In thousands)
Financial assets:
Cash and cash equivalents:
Money market account	$	36,728	$	—	$	—	$	36,728	$	—	$	—	$	36,728





Commercial paper	28,254		—		—		28,254		—		—		28,254

Total included in cash and cash equivalents	64,982		—		—		64,982		—		—		64,982
Marketable securities:
Time deposits	6,645		—		(15)		6,630		—		—		6,630
U.S. treasury securities	14,718		74		—		14,792		—		—		14,792
Corporate debt securities	23,412		—		(97)		—		23,315		—		23,315
Commercial paper	26,142		352		—		26,494		—		—		26,494
Total marketable securities	70,917		426		(112)		47,916		23,315		—		71,231



Total financial assets	$	135,899	$	426	$	(112)	$	112,898	$	23,315	$	—	$	136,213

Schedule of Contractual Maturities of Marketable Securities

The following table summarizes the contractual maturities of marketable securities as of December 31, 2023:


	Amortized cost		Aggregate fair value

	(In thousands)
Financial assets:
Less than one year	$	21,422	$	21,488

Total	$	21,422	$	21,488

Organization and Description of Business	12 Months Ended
Organization and Description of Business	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	1. Organization and Description of Business Bandwidth Inc. (together with its subsidiaries, “Bandwidth” or the “Company”) was founded in July 2000 and incorporated in Delaware on March 29, 2001. The Company’s headquarters are located in Raleigh, North Carolina. The Company is a global cloud-based, software-powered communications platform-as-a-service (“CPaaS”) provider that enables enterprises to create, scale and operate voice or messaging communications services across any mobile application or connected device.

Goodwill and Intangible Assets - Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Line Items]
Total amortization expense	$ 17,274	$ 17,180	$ 19,119
Cost of revenue
Goodwill [Line Items]
Total amortization expense	7,810	7,657	8,543
Sales and marketing
Goodwill [Line Items]
Total amortization expense	$ 9,464	$ 9,523	$ 10,576

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482548/350-20-55-24

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1A

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-2

+ Details

Goodwill and Intangible Assets

12 Months Ended

Dec. 31, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets

7. Goodwill and Intangible Assets

Goodwill

The change in the carrying amounts of goodwill was as follows:


	Total

	(In thousands)



Balance as of December 31, 2021	$	344,423

Foreign currency translation adjustments	(18,018)
Balance as of December 31, 2022	326,405
Foreign currency translation adjustments	9,467
Balance as of December 31, 2023	$	335,872

Intangible Assets

Intangible assets, net consisted of the following as of December 31, 2023:


	Gross Amount		Accumulated Amortization		Net Carrying Value		Amortization Period

	(In thousands)						(In years)
Customer relationships	$	147,426	$	(35,599)	$	111,827	15 - 20



Developed technology	79,702		(25,239)		54,463		10
Other, definite lived	2,828		(2,828)		—		2 - 7
Licenses, indefinite lived	624		—		624		Indefinite







Total intangible assets, net	$	230,580	$	(63,666)	$	166,914

Intangible assets, net consisted of the following as of December 31, 2022:


	Gross Amount		Accumulated Amortization		Net Carrying Value		Amortization Period

	(In thousands)						(In years)
Customer relationships	$	141,146	$	(25,037)	$	116,109	15 - 20



Developed technology	77,409		(16,772)		60,637		10
Other, definite lived	2,828		(2,828)		—		2 - 7
Licenses, indefinite lived	624		—		624		Indefinite







Total intangible assets, net	$	222,007	$	(44,637)	$	177,370

The Company recognized amortization expense as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
Cost of revenue		$	7,810	$	7,657	$	8,543

Sales and marketing		9,464		9,523		10,576

Total amortization expense		$	17,274	$	17,180	$	19,119

The remaining weighted average amortization period for definite lived intangible assets is 10.1 years.

Future estimated amortization expense for definite lived intangible assets is as follows:


	As of December 31,
	2023

	(In thousands)

2024	$	17,625
2025	17,625
2026	17,625
2027	17,625
2028	17,625

Thereafter	78,165
	$	166,290

Basic and Diluted (Loss) Income per Common Share - Components of Basic and Diluted Earnings per Share (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share [Abstract]
Net (loss) income attributable to common stockholders	$ (16,343,000)	$ 19,570,000	$ (27,362,000)
Net (loss) income per share:
Net loss per share, basic (in usd per share)	$ (0.64)	$ 0.77	$ (1.09)
Net loss per share, diluted (in usd per share)	$ (0.64)	$ (0.48)	$ (1.09)
Numerator used to compute net (loss) income per share:
Net gain on extinguishment of debt	$ 0	$ (39,614,000)	$ 0
Interest expense on convertible notes, net of taxes	0	5,147,000	0
Net loss attributable to common stockholders, diluted	$ (16,343,000)	$ (14,897,000)	$ (27,362,000)
Weighted average number of common shares outstanding, basic and diluted
Weighted average number of common shares outstanding, basic (in shares)	25,612,724	25,282,796	25,090,916
Convertible debt conversion	0	5,625,073	0
Weighted average number of common shares outstanding, diluted (in shares)	25,612,724	30,907,869	25,090,916

Financial Statement Components (Tables)

12 Months Ended

Dec. 31, 2023

Financial Statement Components [Abstract]

Schedule of Accounts Receivable, net of Allowances

Accounts receivable, net of allowances consist of the following:



	As of December 31,
	2023		2022

	(In thousands)
Trade accounts receivable	$	35,612	$	40,332
Unbilled accounts receivable	43,631		33,863
Allowance for doubtful accounts and reserve for expected credit losses	(1,128)		(1,191)
Other accounts receivable	40		1,461
Total accounts receivable, net	$	78,155	$	74,465

Components of allowance for doubtful accounts and reserve for expected credit losses are as follows:


	Year ended December 31,
		2023		2022

		(In thousands)
Balance, beginning of period		$	(1,191)	$	(1,661)
Charged to bad debt expense, net of reversals		(733)		(543)
Deductions (1)		807		983
Impact of foreign currency translation		(11)		30



Balance, end of period		$	(1,128)	$	(1,191)

________________________

(1) Write-off of uncollectible accounts after all collection efforts have been exhausted.

Schedule of Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following:



	As of December 31,
	2023		2022

	(In thousands)
Accrued expense	$	40,731	$	29,990
Accrued compensation and benefits	19,142		21,595
Accrued sales, use, VAT and telecommunications related taxes	8,467		7,799



Income tax payable	—		2,235
Other accrued expenses	674		958
Total accrued expenses and other current liabilities	$	69,014	$	62,577

Other Liabilities

Other liabilities consisted of the following:



	As of December 31,
	2023		2022

	(In thousands)
Lease incentive	$	—	$	10,468
Other liabilities	386		708
Total other liabilities	$	386	$	11,176

Stockholders' Equity - Additional Information (Details)	12 Months Ended
Stockholders' Equity - Additional Information (Details)	Dec. 31, 2023 vote $ / shares shares	Dec. 31, 2022 vote $ / shares shares	Dec. 31, 2021 $ / shares	Mar. 31, 2021 $ / shares	Feb. 28, 2020 $ / shares
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, par value (in usd per share) \| $ / shares	$ 0.001	$ 0.001
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Stock split conversion ratio	1
Common stock, dividends declared (in usd per share) \| $ / shares	$ 0	$ 0	$ 0
Class A voting common stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, par value (in usd per share) \| $ / shares	$ 0.001	$ 0.001		$ 0.001	$ 0.001
Common stock voting rights \| vote	1	1
Common stock, shares issued (in shares)	24,206,140	23,379,000
Common stock, shares outstanding (in shares)	24,206,140	23,379,000
Class B voting common stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, par value (in usd per share) \| $ / shares	$ 0.001	$ 0.001
Common stock voting rights \| vote	10	10
Common stock, shares issued (in shares)	1,958,028	1,965,170
Common stock, shares outstanding (in shares)	1,958,028	1,965,170

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2023

Equity [Abstract]

Schedule of Reserved Shares of Common Stock for Issuance

The Company had reserved shares of Class A common stock for issuance under stock-based award agreements as follows:



	As of December 31,
	2023	2022
Stock options issued and outstanding	97,480	159,741
Nonvested restricted stock units issued and outstanding	5,066,159	2,607,106
Stock-based awards available for grant under the 2017 Plan	2,330,616	1,879,368
Total	7,494,255	4,646,215

- Definition

Tabular disclosure of an entity's stock, including par or stated value per share, number and dollar amount of share subscriptions, shares authorized, shares issued, shares outstanding, number and dollar amount of shares held in an employee trust, dividend per share, total dividends, share conversion features, par value plus additional paid in capital, the value of treasury stock and other information necessary to a fair presentation, and EPS information. Stock by class includes common, convertible, and preferred stocks which are not redeemable or redeemable solely at the option of the issuer. Includes preferred stock with redemption features that are solely within the control of the issuer and mandatorily redeemable stock if redemption is required to occur only upon liquidation or termination of the reporting entity. If more than one issue is outstanding, state the title of each issue and the corresponding dollar amount; dollar amount of any shares subscribed but unissued and the deduction of subscriptions receivable there from; number of shares authorized, issued, and outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(27))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-3

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-4

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-5

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481142/505-10-45-2

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-10

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-8

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480244/480-10-S99-1

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-6

Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-7

+ Details

Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of options outstanding
Beginning balance (in shares)	159,741
Granted (in shares)	0
Exercised (in shares)	(61,349)
Forfeited or expired (in shares)	(912)
Ending balance (in shares)	97,480	159,741
Options vested and exercisable (in shares)	97,480
Options vested and expected to vest (in shares)	97,480
Weighted- average exercise price (Per share)
Beginning balance (in usd per share)	$ 10.42
Granted (in usd per share)	0
Exercised (in usd per share)	6.74
Forfeited or expired (in usd per share)	9.46
Ending balance (in usd per share)	12.75	$ 10.42
Weighted-average exercise price, Options vested and exercisable (in usd per share)	12.75
Weighted-average exercise price, Options vested and expected to vest (in usd per share)	$ 12.75
Weighted- average remaining contract life (In years)
Outstanding (in years)	2 years 11 months 19 days	2 years 6 months 25 days
Options vested and exercisable at December 31, 2023	2 years 11 months 19 days
Options vested and expected to vest as of December 31, 2023	2 years 11 months 19 days
Aggregate intrinsic value (In thousands)
Options outstanding	$ 332	$ 2,001
Options vested and exercisable at December 31, 2023	332
Options vested and expected to vest as of December 31, 2023	$ 332

Stockholders' Equity

12 Months Ended

Dec. 31, 2023

Equity [Abstract]

Stockholders' Equity

10. Stockholders’ Equity

Preferred Stock

As of December 31, 2023 and 2022, the Company had authorized 10,000,000 shares of undesignated preferred stock, par value $0.001, of which no shares were issued and outstanding.

Common Stock

As of December 31, 2023 and 2022, the Company had authorized 100,000,000 shares of Class A common stock, par value $0.001 per share and 20,000,000 shares of Class B common stock, par value $0.001 per share.

Shares of Class B common stock are convertible into shares of Class A common stock on a 1:1 basis upon the stockholder’s voluntary written notice to the Company’s transfer agent or a transfer by the stockholder, subject to limited exceptions for transfers for estate planning purposes.

Voting Rights

The holders of Class A common stock and Class B common stock have identical rights, except that holders of Class A voting common stock are entitled to one vote per share of Class A common stock and holder of Class B common stock are entitled to ten votes per share of Class B common stock.

Dividends

Any dividends or distributions paid or payable to the holders of shares of Class A common stock and Class B common stock shall be paid pro-rata, on an equal priority. During the years ended December 31, 2023, 2022 and 2021, no dividends were declared. Dividend payments are not subject to restriction.

Reserved Shares

The Company had reserved shares of Class A common stock for issuance under stock-based award agreements as follows:



	As of December 31,
	2023	2022
Stock options issued and outstanding	97,480	159,741
Nonvested restricted stock units issued and outstanding	5,066,159	2,607,106
Stock-based awards available for grant under the 2017 Plan	2,330,616	1,879,368
Total	7,494,255	4,646,215

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481004/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

+ Details

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Disaggregation of Revenue

Revenue consists primarily of two categories: (1) cloud communications and (2) messaging surcharges, which are described and quantified below.


	Year ended December 31,
	2023		2022		2021

	(In thousands)

Cloud communications	$	478,892	$	474,576	$	449,656
Messaging surcharges	122,225		98,576		41,251
Total revenue	$	601,117	$	573,152	$	490,907

Schedule of Contract Assets and Liabilities

The following table provides information about receivables and contract liabilities from contracts with customers:


	As of December 31,
	2023		2022

	(In thousands)
Receivables (1)	$	78,155	$	74,465
Contract liabilities (2)	16,465		15,487

________________________

(1) Included in accounts receivable, net of allowance for doubtful accounts on the consolidated balance sheets.

(2) Included in current portion of deferred revenue and deferred revenue, net of current portion on the consolidated balance sheets.

Employee Benefit Plans - Summary of Defined Benefit Plan With Accumulated Benefit Obligation in Excess of Plan Assets (Details) - Non-U.S. - Pension Plan - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan, Plan Assets, Category [Line Items]
Projected benefit obligation	$ 3,927	$ 3,502
Accumulated benefit obligation	3,623	3,265
Fair value of plan assets	$ 3,607	$ 3,181

Debt - Revolving Loan (Details)	Aug. 01, 2023 USD ($) qtr	Dec. 31, 2023 USD ($)	Mar. 14, 2023 USD ($)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Outstanding unamortized loan fees		$ 600,000		$ 400,000
Bank of America Credit Agreement \| Line of Credit \| Revolving Loan
Debt Instrument [Line Items]
Borrowing capacity	$ 50,000,000
Accordion feature, increase limit	$ 25,000,000
Days prior to maturity date	91 days
Covenant, consecutive quarters \| qtr	4
Line of credit		0
Bank of America Credit Agreement \| Line of Credit \| Revolving Loan \| Minimum
Debt Instrument [Line Items]
Unused portion of borrowing commitment	0.05%
Bank of America Credit Agreement \| Line of Credit \| Revolving Loan \| Maximum
Debt Instrument [Line Items]
Unused portion of borrowing commitment	0.0625%
Bank of America Credit Agreement \| Line of Credit \| Revolving Loan \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Additional basis spread on variable rate	0.10%
Bank of America Credit Agreement \| Line of Credit \| Revolving Loan \| Secured Overnight Financing Rate (SOFR) \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Bank of America Credit Agreement \| Line of Credit \| Revolving Loan \| Secured Overnight Financing Rate (SOFR) \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.75%
Bank of America Credit Agreement \| Line of Credit \| Revolving Loan \| Base rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Bank of America Credit Agreement \| Line of Credit \| Revolving Loan \| Base rate \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Bank of America Credit Agreement \| Line of Credit \| Credit commitments
Debt Instrument [Line Items]
Borrowing capacity	$ 15,000,000
Bank of America Credit Agreement \| Line of Credit \| Swing line
Debt Instrument [Line Items]
Borrowing capacity	$ 5,000,000
Silicon Valley Bank Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Line of credit			$ 0
Prepaid expenses and other current assets
Debt Instrument [Line Items]
Outstanding unamortized loan fees		100,000		200,000
Other long-term assets
Debt Instrument [Line Items]
Outstanding unamortized loan fees		$ 500,000		$ 200,000

Basic and Diluted (Loss) Income per Common Share

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Basic and Diluted (Loss) Income per Common Share

15. Basic and Diluted (Loss) Income per Common Share

Basic net (loss) income per share is computed by dividing net (loss) income by the weighted-average number of shares of common stock outstanding during the period. The Company is in a net loss position for the years ended December 31, 2023 and 2021, and therefore diluted shares equals basic shares.

The components of basic and diluted (loss) income per share are as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands, except share and per share amounts)
Earnings per share


Net (loss) income attributable to common stockholders		$	(16,343)	$	19,570	$	(27,362)
Net (loss) income per share:
Basic		$	(0.64)	$	0.77	$	(1.09)
Diluted		$	(0.64)	$	(0.48)	$	(1.09)
Numerator used to compute net (loss) income per share:
Basic		$	(16,343)	$	19,570	$	(27,362)
Net gain on extinguishment of debt, net of taxes		—		(39,614)		—
Interest expense on convertible notes, net of taxes		—		5,147		—
Diluted (1)		$	(16,343)	$	(14,897)	$	(27,362)














Weighted average number of common shares outstanding:
Basic		25,612,724		25,282,796		25,090,916

Convertible debt conversion		—		5,625,073		—



Diluted		25,612,724		30,907,869		25,090,916

________________________

(1) Upon the adoption of ASU 2020-06, net income is adjusted for the reversal of the net gain on extinguishment of debt and add back of interest expense as part of the calculation for diluted Non-GAAP earnings per share. See Note 8, “Debt,” to the consolidated financial statements, for additional details on the adoption of ASU 2020-06.

The following common share equivalents were excluded from the weighted average shares used to calculate net (loss) income per common share because their effects would have been anti-dilutive:


	As of December 31,
	2023	2022	2021
Stock options issued and outstanding	97,480	159,741	180,209
Restricted stock units issued and outstanding	5,911,794	2,607,106	344,486
Convertible senior notes (1) (2)	3,442,229	—	987,149
Total	9,451,503	2,766,847	1,511,844

________________________

(1) As of December 31, 2022, subsequent to adopting ASU 2020-06 as of January 1, 2022, the Company used the if-converted method to calculate the dilutive impact of the 2026 Convertible Notes and 2028 Convertible Notes on diluted income per share, if applicable. The Company expected to settle the principal amount of these notes in cash and any excess in shares of the Company’s Class A common stock. The diluted shares were calculated based on the initial conversion rate of 10.9857 and 5.5781 shares per $0.001 of the aggregate principal amount for the 2026 Convertible Notes and 2028 Convertible Notes, respectively. See Note 8, “Debt” to the consolidated financial statements, for additional details on the adoption of ASU 2020-06 and for additional details on the Company’s Convertible Notes.

(2) As of December 31, 2021, the Company used the treasury stock method to calculate the dilutive impact of the 2026 Convertible Notes and the 2028 Convertible Notes because at that time the Company expected to settle the principal amount of these notes in cash and any excess in shares of the Company’s Class A common stock. As of December 31, 2021, the conversion spread, calculated using the average market price of Class A common stock during the period consistent with the treasury stock method, had a dilutive impact for the 2026 Convertible Notes on diluted net income per share of Class A common stock when the average market price of the Company’s Class A common stock for a given period exceeded the conversion price of $91.03 per share. As of December 31, 2021, the conversion spread for the 2028 Convertible Notes was anti-dilutive as the average market price of the Company’s Class A common stock for a given period did not exceed the conversion price of $179.27 per share.

Geographic Information - Reconciliation of Revenue by Geographic Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 601,117	$ 573,152	$ 490,907
Assets	1,101,048	929,318
North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	514,048	484,105	433,463
Rest of World
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	87,069	89,047	$ 57,444
Assets	$ 4,500	$ 9,100

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 810
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (bb)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481203/810-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 810
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 25
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481231/810-10-45-25

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-28

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481372/852-10-55-10

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480167/946-830-55-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(8))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(18))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 13: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 14: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(5))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(B))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(5))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B

Reference 23: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481404/852-10-50-7

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-30

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 26: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Debt

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Debt

8. Debt

Revolving Credit Facility

On August 1, 2023, the Company entered into a credit agreement (the “Credit Agreement”) among the Company, as borrower, the lenders from time to time party thereto, and Bank of America, N.A., as administrative agent, swingline lender and letters of credit issuer. The Credit Agreement provides for a $50.0 million revolving credit facility (the “Credit Facility”), including a $15.0 million sublimit for the issuance of letters of credit and a swingline subfacility of up to $5.0 million. The Credit Facility has an accordion feature that allows for an increase in the total borrowing size up to $25.0 million, subject to certain conditions. The Credit Facility matures on the earlier of (a) August 1, 2028 or (b) the date that is 91 days prior to the scheduled maturity date or mandatory conversion date of any of the Company’s outstanding convertible notes. Interest on borrowings under the Credit Facility accrues at an annual rate tied to a base rate or the Secured Overnight Financing Rate (“SOFR”), at the Company’s election. Loans based on SOFR bear interest at a rate equal to term SOFR for the applicable interest period plus 10 basis points plus an applicable margin between 2.25% and 2.75%, and loans based on the base rate bear interest at a rate equal to the base rate plus an applicable margin between 1.25% and 1.75%, in each case of the foregoing, depending upon the Company’s consolidated EBITDA for the most recent period of four consecutive fiscal quarters for which financial statements have been delivered under the Credit Agreement. The Company is required to pay a quarterly commitment fee equal to between 0.05% and 0.0625% on the unused portion of the borrowing commitment, depending upon the Company’s consolidated EBITDA for the most recent period of four consecutive fiscal quarters for which financial statements have been delivered under the Credit Agreement.

On March 10, 2023, Silicon Valley Bank (“SVB”) was closed by the California Department of Financial Protection and Innovation, which appointed the Federal Deposit Insurance Corporation as receiver. As a result, SVB ceased normal banking operations for a period of time. Given these circumstances, on March 14, 2023 (the “Notice Date”), the Company gave notice to SVB of its desire and intent to terminate the commitments (the “Termination”) under that certain credit agreement, dated as of June 6, 2022, among the Company, as borrower, the lenders from time to time party thereto, and SVB, as administrative agent, issuing lender and swingline lender. As of the Notice Date, there were no outstanding borrowings under this credit agreement. The Termination became effective on March 15, 2023.

As of December 31, 2023, unamortized debt issuance costs were $0.6 million, of which $0.1 million were included in prepaid expenses and other current assets and $0.5 million were included in other long-term assets. As of December 31, 2022, unamortized debt issuance costs were $0.4 million, of which $0.2 million were included in prepaid expenses and other current assets and $0.2 million were included in other long-term assets.

As of December 31, 2023, there were no borrowings under the Credit Facility and the Company was in compliance with all financial and non-financial covenants for all periods presented.

Convertible Senior Notes and Capped Call Transactions

2026 Convertible Notes

In February 2020, the Company issued $400.0 million aggregate principal amount of 0.25% Convertible Notes due 2026 in a private placement to qualified institutional buyers pursuant to Rule 144A under the Securities Act (the “2026 Convertible Notes”). The interest on the 2026 Convertible Notes is payable semi-annually in arrears on March 1 and September 1 of each year, beginning on September 1, 2020. The 2026 Convertible Notes will mature on March 1, 2026, unless earlier repurchased, redeemed by the Company, or converted pursuant to their terms. The total net proceeds from the 2026 Convertible Notes, after deducting initial purchaser discounts, costs related to the 2026 Capped Calls (as defined herein), and debt issuance costs, paid by the Company, were approximately $344.7 million. The excess of the principal amount of the liability component over its carrying

amount, or the debt discount, was amortized to interest expense at an annual effective interest rate of 0.509% over the contractual terms of the 2026 Convertible Notes.

Each $1,000 principal amount of the 2026 Convertible Notes is initially convertible into 10.9857 shares of the Company’s Class A common stock, par value $0.001 per share, which is equivalent to an initial conversion price of approximately $91.03 per share.

During March 2023, the Company entered into separate, privately negotiated repurchase agreements with a limited number of holders of the 2026 Convertible Notes to repurchase approximately $65.0 million aggregate principal amount of the 2026 Convertible Notes for an aggregate cash price of approximately $51.3 million. These repurchases closed on March 6, 2023. The Company entered into similar agreements to repurchase approximately $160.0 million aggregate principal amount of the 2026 Convertible Notes for an aggregate cash price of approximately $117.2 million that closed in November 2022. Following these repurchases, approximately $175.0 million principal amount of the 2026 Convertible Notes remain outstanding. The Company had previously entered into capped call transactions with certain financial institutions in connection with the 2026 Convertible Notes. All of these transactions are expected to remain in effect notwithstanding the repurchases. The difference between the consideration used to repurchase the 2026 Convertible Notes and the carrying value of the 2026 Convertible Notes resulted in gains of $12.8 million and $40.2 million recorded within net gain on extinguishment of debt on the Company’s consolidated statements of operations for the years ended December 31, 2023 and 2022, respectively.

2028 Convertible Notes

In March 2021, the Company issued $250.0 million aggregate principal amount of 0.50% Convertible Notes due 2028 in a private placement to qualified institutional buyers pursuant to Rule 144A under the Securities Act (the “2028 Convertible Notes” and, together with the 2026 Convertible Notes, the “Convertible Notes”). The interest on the 2028 Convertible Notes is payable semi-annually in arrears on April 1 and October 1 of each year, beginning on October 1, 2021. The 2028 Convertible Notes will mature on April 1, 2028, unless earlier repurchased, redeemed by the Company, or converted pursuant to their terms. The total net proceeds from the 2028 Convertible Notes, after deducting initial purchaser discounts, costs related to the 2028 Capped Calls (as defined herein), and debt issuance costs, paid by the Company, were approximately $217.0 million. The excess of the principal amount of the liability component over its carrying amount, or the debt discount, was amortized to interest expense at an annual effective interest rate of 0.442% over the contractual terms of the 2028 Convertible Notes.

Each $1,000 principal amount of the 2028 Convertible Notes is initially convertible into 5.5781 shares of the Company’s Class A common stock, par value $0.001 per share, which is equivalent to an initial conversion price of approximately $179.27 per share.

Other Terms of the Convertible Notes

The Convertible Notes are effectively subordinated to the Company’s future senior secured indebtedness to the extent of the value of the collateral securing that indebtedness. The Convertible Notes are the senior, unsecured obligations of the Company and are equal in right of payment with the Company’s future senior unsecured indebtedness, if any, senior in right of payment to the Company’s existing and future indebtedness that is expressly subordinated to the Convertible Notes and the Convertible Notes will be structurally subordinated to all existing and future indebtedness and other liabilities, including trade payables, and preferred equity, if any, of the Company’s subsidiaries. The Convertible Notes may bear special interest under specified circumstances relating to the Company’s failure to comply with its reporting obligations under the indenture governing the applicable Convertible Notes (each, a “Notes Indenture” and collectively, the “Notes Indentures”) or if the Convertible Notes are not freely tradeable as required by the applicable Notes Indenture.

The conversion rate is subject to adjustment upon the occurrence of certain specified events but will not be adjusted for any accrued and unpaid interest. In addition, upon the occurrence of a make-whole fundamental change (which includes the calling of any Convertible Notes for redemption), as defined in the applicable Notes Indenture, the Company will, in certain circumstances, increase the conversion rate by a number of additional shares for a

holder that elects to convert its Convertible Notes in connection with such make-whole fundamental change or during the relevant redemption period.

The Company may redeem the Convertible Notes, in whole or in part, at its option at any time, and from time to time, on or after (i) March 6, 2023 for the 2026 Convertible Notes, or ii) after April 6, 2025 for the 2028 Convertible Notes, in each case, on or before the fortieth (40th) scheduled trading day immediately before the maturity date, at a cash redemption price equal to 100% of the principal amount thereof, plus accrued and unpaid interest, if any, to, but excluding the redemption date, if the last reported sale price of the Class A common stock has exceeded 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive), including the trading date immediately preceding the date on which the Company provides notice of redemption, during any 30 consecutive trading days ending on, and including, the trading date immediately before the date on which the Company provides the related redemption notice. No sinking fund is provided for the Convertible Notes.

The Convertible Notes will be convertible at certain times and upon the occurrence of certain events in the future. Further, on or after September 1, 2025 for the 2026 Convertible Notes, and on or after October 1, 2027 for the 2028 Convertible Notes, in each case, until the close of business on the second scheduled trading day immediately preceding the maturity date, holders of the Convertible Notes may convert all or a portion of their Convertible Notes regardless of these conditions. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of Class A common stock, or a combination of cash and shares of Class A common stock, at the Company’s election. It is the Company’s current intent to settle the principal amount of the Convertible Notes with cash.

During the years ended December 31, 2023 and 2022, the conditions allowing the holders of the 2026 Convertible Notes and the 2028 Convertible Notes to convert were not met. The Convertible Notes may be convertible thereafter if one or more of the conversion conditions specified in each respective Notes Indenture are satisfied during future measurement periods. The Company continues to classify the Convertible Notes as a long-term liability in its consolidated balance sheets as of December 31, 2023, based on contractual settlement provisions.

Upon the occurrence of a fundamental change (as defined in the applicable Notes Indenture) prior to the maturity date, holders may require the Company to repurchase all or a portion of the 2026 Convertible Notes or 2028 Convertible Notes for cash at a price equal to the principal amount of the Convertible Notes to be repurchased, plus any accrued and unpaid interest to, but excluding, the fundamental change repurchase date.

The net carrying amount of the liability components of the Convertible Notes were as follows:



	As of December 31,
	2023		2022

2026 Convertible Notes:	(In thousands)
Principal	$	175,000	$	240,000

Unamortized debt issuance costs	(1,891)		(3,805)
2026 Convertible Notes net carrying amount	173,109		236,195

2028 Convertible Notes:
Principal	250,000		250,000

Unamortized debt issuance costs	(4,583)		(5,649)
2028 Convertible Notes net carrying amount	245,417		244,351
Total net carrying amount	$	418,526	$	480,546

The following table sets forth the interest expense recognized related to the Convertible Notes:


	Year ended December 31,
		2023		2022

2026 Convertible Notes:		(In thousands)
Contractual interest expense		$	465	$	997

Amortization of debt issuance costs		940		1,915
Total interest expense related to the 2026 Convertible Notes		1,405		2,912

2028 Convertible Notes:
Contractual interest expense		1,250		1,250

Amortization of debt issuance costs		1,064		1,062
Total interest expense related to the 2028 Convertible Notes		2,314		2,312
Total interest expense		$	3,719	$	5,224

On January 1, 2022, the Company adopted ASU 2020-06, Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2020-06”), using the modified retrospective approach resulting in decreases in accumulated deficit of $8.8 million, additional paid in capital of $156.2 million, and deferred tax liability of $1.0 million. The Company also recorded an increase in the Convertible Notes balance of $148.4 million as a result of the reversal of the separation of the convertible debt between debt and equity. The adoption of this standard decreased the amount of non-cash interest expense to be recognized in current and future periods as a result of eliminating the discount associated with the equity component. For the years ended December 31, 2023 and 2022, the combined interest expense of the Convertible Notes was $29.2 million and $27.2 million lower, respectively, upon the adoption of ASU 2020-06. The number of diluted shares increased as a result of transitioning from the treasury stock method to the as-if converted method which impacted the earnings per share for the year ended December 31, 2022. The transition did not impact the years ended December 31, 2023 and 2021, as the Company incurred a net loss in both reporting periods.

Capped Calls

In connection with the offering of the 2026 Convertible Notes and the 2028 Convertible Notes, the Company entered into privately negotiated capped call transactions with certain counterparties (the “2026 Capped Calls” and the “2028 Capped Calls,” respectively and, collectively, the “Capped Calls”). The initial strike price of the Convertible Notes corresponds to the initial conversion price of the 2026 Convertible Notes and the 2028 Convertible Notes. The Capped Calls are generally intended to reduce or offset the potential dilution to the Class A common stock upon any conversion of the 2026 Convertible Notes and 2028 Convertible Notes with such reduction or offset, as the case may be, subject to a cap based on the cap price. The Capped Calls expire on the earlier of (i) the last day on which any convertible securities remain outstanding and (ii) March 1, 2026 for the 2026 Capped Calls and April 1, 2028 for the 2028 Capped Calls, subject to earlier exercise. The Capped Calls are subject to either adjustment or termination upon the occurrence of specified extraordinary events affecting the Company, including a merger event, a tender offer, and a nationalization, insolvency or delisting involving the Company. In addition, the Capped Calls are subject to certain specified additional disruption events that may give rise to a termination of the Capped Calls, including changes in law, insolvency filings, and hedging disruptions. The Capped Call transactions are recorded in stockholders’ equity and are not accounted for as derivatives. The net cost to purchase the Capped Calls was recorded as a reduction to additional paid-in capital in the accompanying consolidated balance sheets.

The following table sets forth key terms and costs incurred for the Capped Calls related to the Convertible Notes as of December 31, 2023:


	2026 Convertible Notes		2028 Convertible Notes

	(In thousands, except share and per share amounts)
Initial approximate strike price per share, subject to certain adjustments	$	91.03	$	179.27
Initial cap price per share, subject to certain adjustments	$	137.40	$	260.76
Net costs incurred	$	43,320	$	25,500
Class A common stock covered, subject to anti-dilution adjustments	1,922,498		1,394,525

All of the Capped Calls were outstanding as of December 31, 2023.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//470/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

Income Taxes - Components of (Provision) Benefit for Income Taxes from Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current:
Federal	$ (653)	$ (2,717)	$ (2,713)
State	(1,309)	(803)	(145)
Foreign	(2,219)	(815)	(1,627)
Total	(4,181)	(4,335)	(4,485)
Deferred:
Federal	(75)	1,004	(364)
State	0	(1)	0
Foreign	7,216	5,596	8,682
Total	7,141	6,599	8,318
Income tax (provision) benefit	$ 2,960	$ 2,264	$ 3,833

Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Concentration Risk [Line Items]
Revenue	$ 601,117	$ 573,152	$ 490,907
Recognized revenue	5,800
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Concentration Risk [Line Items]
Remaining performance obligation, amount	$ 8,100
Remaining performance obligation period	12 months
CPaaS, Usage-Based Fees
Concentration Risk [Line Items]
Revenue	$ 346,900	354,000	355,300
CPaaS, Service Fees
Concentration Risk [Line Items]
Revenue	$ 132,000	$ 120,600	$ 94,400

- Definition

+ References

+ Details

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (16,343)	$ 19,570	$ (27,362)
Other comprehensive income (loss)
Unrealized (loss) gain on marketable securities, net of income taxes	(248)	314	0
Foreign currency translation, net of income taxes	15,698	(31,855)	(41,150)
Unrealized (loss) gain on employee benefit plan, net	(30)	367	169
Total other comprehensive income (loss)	15,420	(31,174)	(40,981)
Total comprehensive income (loss)	$ (923)	$ (11,604)	$ (68,343)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Consolidated Statements of Operations - USD ($)	12 Months Ended
Consolidated Statements of Operations - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Revenue	$ 601,117,000	$ 573,152,000	$ 490,907,000
Cost of revenue	364,960,000	334,799,000	277,094,000
Gross profit	236,157,000	238,353,000	213,813,000
Operating expenses
Research and development	104,188,000	97,990,000	69,505,000
Sales and marketing	102,063,000	96,658,000	82,333,000
General and administrative	65,363,000	68,029,000	64,212,000
Total operating expenses	271,614,000	262,677,000	216,050,000
Operating loss	(35,457,000)	(24,324,000)	(2,237,000)
Other (expense) income, net
Net gain on extinguishment of debt	12,767,000	40,205,000	0
Gain on business interruption insurance recoveries	4,000,000	0	0
Interest income (expense), net	(808,000)	(3,048,000)	(28,784,000)
Other income (expense), net	195,000	4,473,000	(174,000)
Total other (expense) income, net	16,154,000	41,630,000	(28,958,000)
(Loss) income before income taxes	(19,303,000)	17,306,000	(31,195,000)
Income tax (provision) benefit	2,960,000	2,264,000	3,833,000
Net (loss) income	$ (16,343,000)	$ 19,570,000	$ (27,362,000)
Net loss per share, basic and diluted
Net loss per share, basic (in usd per share)	$ (0.64)	$ 0.77	$ (1.09)
Net loss per share, diluted (in usd per share)	$ (0.64)	$ (0.48)	$ (1.09)
Numerator used to compute net loss per share:
Net (loss) income attributable to common stockholders	$ (16,343,000)	$ 19,570,000	$ (27,362,000)
Net loss attributable to common stockholders, diluted	$ (16,343,000)	$ (14,897,000)	$ (27,362,000)
Weighted average number of common shares outstanding, basic and diluted
Weighted average number of common shares outstanding, basic (in shares)	25,612,724	25,282,796	25,090,916
Weighted average number of common shares outstanding, diluted (in shares)	25,612,724	30,907,869	25,090,916

Financial Statement Components - Other Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financial Statement Components [Abstract]
Lease incentive	$ 0	$ 10,468
Other liabilities	386	708
Other liabilities	$ 386	$ 11,176

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 131,987	$ 113,641
Marketable securities	21,488	71,231
Accounts receivable, net of allowance for doubtful accounts	78,155	74,465
Deferred costs	4,155	3,566
Prepaid expenses and other current assets	16,990	16,705
Total current assets	252,775	279,608
Property, plant and equipment, net	177,864	99,753
Operating right-of-use asset, net	157,507	9,993
Intangible assets, net	166,914	177,370
Deferred costs, non-current	4,586	4,938
Other long-term assets	5,530	31,251
Goodwill	335,872	326,405
Total assets	1,101,048	929,318
Current liabilities:
Accounts payable	34,208	26,750
Accrued expenses and other current liabilities	69,014	62,577
Current portion of deferred revenue	8,059	7,181
Advanced billings	6,027	10,049
Operating lease liability, current	5,463	7,450
Total current liabilities	122,771	114,007
Other liabilities	386	11,176
Operating lease liability, net of current portion	220,548	4,640
Deferred revenue, net of current portion	8,406	8,306
Deferred tax liability	33,021	38,466
Convertible senior notes	418,526	480,546
Total liabilities	803,658	657,141
Commitments and contingencies
Stockholders’ equity:
Preferred stock: $0.001 par value; 10,000,000 shares authorized; 0 shares issued and outstanding	0	0
Additional paid-in capital	391,048	364,913
Accumulated deficit	(64,890)	(48,547)
Accumulated other comprehensive loss	(28,794)	(44,214)
Total stockholders’ equity	297,390	272,177
Total liabilities and stockholders’ equity	1,101,048	929,318
Class A voting common stock
Stockholders’ equity:
Class A and Class B common stock	24	23
Class B voting common stock
Stockholders’ equity:
Class A and Class B common stock	$ 2	$ 2

Leases

12 Months Ended

Dec. 31, 2023

Leases [Abstract]

Leases

5. Leases

Right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term, and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. The Company determines if an arrangement is a lease at inception. ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. Operating lease expense attributable to lease payments is recognized on a straight-line basis over the lease term and is part of allocated facilities costs based on employee headcount within the cost of revenue, research and development, sales and marketing, and general and administrative expense categories on the Company’s consolidated statements of operations. Finance leases result in the recognition of depreciation expense, which is recognized on a straight-line basis over the expected life of the leased asset, and interest expense, which is recognized following an effective interest rate method. Depreciation expense attributable to finance leases is included in operating expenses on the Company’s consolidated statements of operations. The Company presents the operating leases in long-term assets and current and long-term liabilities in the accompanying consolidated balance sheets. Finance leases are reported in property, plant and equipment, net, accrued expenses and other current liabilities, and other liabilities on the Company’s consolidated balance sheets.

The Company has entered into various operating lease agreements for office space and finance lease agreements for automobiles.

The Company previously sub-leased approximately 17,073 square feet of office space to a related party, Relay, Inc. (f/k/a Republic Wireless, Inc.) (“Relay”). The lease term under this non-cancellable lease expired in July 2022.

The Company primarily leases facilities for office space under non-cancelable operating leases for its U.S. and international locations. As of December 31, 2023, non-cancelable leases expire on various dates between 2024 and 2043, some of which include options to extend the leases for up to 20 years.

The components of lease expense recorded in the consolidated statements of operations were as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
Operating lease cost		$	15,655	$	7,750	$	6,818





Sublease income		—		(206)		(384)
Total net lease cost		$	15,655	$	7,544	$	6,434

During the years ended December 31, 2023, 2022 and 2021, short-term operating lease expense was $0.6 million, $0.6 million, and $1.3 million, respectively.

Operating lease assets are recorded net of accumulated amortization of $20.3 million and $17.7 million as of December 31, 2023 and 2022, respectively.

Other supplemental information related to operating leases were as follows:


	Year ended December 31,
		2023		2022		2021








Weighted average remaining lease term (in years)		19.30		2.12		2.95



Weighted average discount rate		8.76	%	4.58	%	4.78	%

Maturities of operating lease liabilities were as follows:


	As of December 31,
	2023


	(In thousands)


2024	$	23,313
2025	22,277
2026	21,722
2027	22,122
2028	22,462
Thereafter	378,808
Total lease payments	490,704
Less: imputed interest	(264,693)

Total lease obligations	226,011
Less: current obligations	(5,463)
Long-term lease obligations	$	220,548

New Corporate Headquarters

On August 1, 2023, the Company commenced a lease for a new corporate headquarters in Raleigh, North Carolina. The lease term will continue for a period of twenty (20) years (the “Initial Term”). The Company has the option to renew the Initial Term for two ten-year periods at a rental rate equal to 100% of the then-prevailing market rental rate for comparable buildings in the Raleigh, North Carolina, market. The Company relocated its corporate headquarters to the leased property during the third quarter of 2023.

Upon commencement of the lease, the Company recognized ROU assets of $156.0 million and operating lease liabilities of $223.1 million. The operating lease liabilities include $67.8 million of incentives provided by the landlord throughout development of the new corporate headquarters. Assets obtained through lease incentives are reported in property, plant and equipment, net, on the consolidated balance sheets. The Company also has recorded $2.5 million in security deposits and $1.0 million in escrow deposits to fund additional improvements. Deposits are reported as a component of other long-term assets on the Company’s consolidated balance sheets.

Leases

5. Leases

The Company has entered into various operating lease agreements for office space and finance lease agreements for automobiles.

The components of lease expense recorded in the consolidated statements of operations were as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
Operating lease cost		$	15,655	$	7,750	$	6,818





Sublease income		—		(206)		(384)
Total net lease cost		$	15,655	$	7,544	$	6,434

During the years ended December 31, 2023, 2022 and 2021, short-term operating lease expense was $0.6 million, $0.6 million, and $1.3 million, respectively.

Operating lease assets are recorded net of accumulated amortization of $20.3 million and $17.7 million as of December 31, 2023 and 2022, respectively.

Other supplemental information related to operating leases were as follows:


	Year ended December 31,
		2023		2022		2021








Weighted average remaining lease term (in years)		19.30		2.12		2.95



Weighted average discount rate		8.76	%	4.58	%	4.78	%

Maturities of operating lease liabilities were as follows:


	As of December 31,
	2023


	(In thousands)


2024	$	23,313
2025	22,277
2026	21,722
2027	22,122
2028	22,462
Thereafter	378,808
Total lease payments	490,704
Less: imputed interest	(264,693)

Total lease obligations	226,011
Less: current obligations	(5,463)
Long-term lease obligations	$	220,548

New Corporate Headquarters

Employee Benefit Plans

12 Months Ended

Dec. 31, 2023

Retirement Benefits [Abstract]

Employee Benefit Plans

13. Employee Benefit Plans

The Company sponsors a U.S. defined contribution 401(k), which allows eligible U.S.-based employees to defer a portion of their compensation. The Company, at its discretion, may make matching contributions. With the acquisition of Voxbone S.A. on November 1, 2020, the Company assumed sponsorship for Voxbone S.A.’s U.S. defined contribution 401(k). In connection with that acquisition, the Company also assumed sponsorship for a non-U.S. defined contribution plan for which it pays fixed contributions into a separate entity. The Company has no legal or constructive obligations to pay further contributions if the fund does not hold sufficient assets to pay all employees the benefits relating to employee service in the current or prior periods. The contributions are recognized as employee benefit expense when they are due. The Company made matching contributions for the defined contribution plans of $4.8 million, $4.6 million, and $3.8 million for the years ended December 31, 2023, 2022 and 2021, respectively.

In addition, as a result of the acquisition of Voxbone S.A., the Company assumed sponsorship for Voxbone S.A.’s non-U.S. defined benefit pension plans. The liability recognized is the present value of the defined benefit obligation at the end of the reporting period less the fair value of the plan assets and is included in other liabilities in the accompanying consolidated balance sheets. The defined benefit obligation is calculated annually by an independent actuary using the Projected Unit Credit Method.

The following table summarizes information for the pension plans:


	As of December 31,
	2023		2022

	(In thousands)
Change in benefit obligation:
Benefit obligation at beginning of year	$	3,502	$	3,874
Service cost	264		268
Interest cost	146		35
Actuarial loss (gain)	13		(418)
Benefits paid	(41)		—
Taxes, insurance premiums and administrative expenses	(61)		(50)

Impact of foreign currency translation	104		(207)
Benefit obligation at end of year	$	3,927	$	3,502

Change in plan assets:
Fair value of plan assets at beginning of year	$	3,181	$	2,958
Return on plan assets	41		26
Actuarial gain	—		72
Employer contribution	393		332

Benefits paid	(41)		—
Taxes, insurance premiums and administrative expenses	(61)		(50)
Impact of foreign currency translation	94		(157)
Fair value of plan assets at end of year	3,607		3,181
Funded status, net liability	$	320	$	321

The Company’s pension liability for the Company’s non-U.S. defined benefit pension plans was $0.3 million as of December 31, 2023 and 2022, which is included in other liabilities on the accompanying consolidated balance sheets.

The following table summarizes information for the Company’s pension plans with an accumulated benefit obligation in excess of plan assets:


	As of December 31,
	2023		2022

	(In thousands)
Projected benefit obligation	$	3,927	$	3,502
Accumulated benefit obligation	3,623		3,265
Fair value of plan assets	3,607		3,181

The Company reports the service cost component of net periodic benefit cost in the same line item as other compensation costs arising from the services rendered by the employee and records the other components of net periodic benefit cost in other income (expense), net.

Pretax amounts for net periodic benefit cost and other amounts for the defined benefit pension plans consisted of the following components:


	Year ended December 31,
	2023		2022		2021

	(In thousands)
Service cost	$	264	$	268	$	396
Interest cost	146		35		21
Return on plan assets	(41)		(26)		(14)
Amortization of actuarial gain	(27)		—		—
Net periodic pension cost	342		277		403
Changes in plan assets and benefit obligations included in other comprehensive loss:
Unrecognized net actuarial (gain) loss beginning of year	(705)		(227)		17
Actuarial gain recognized during year	27		—		—
Actuarial loss (gain) on benefit obligation	13		(418)		(237)
Actuarial gain on fair value of plan assets	—		(72)		(6)
Impact of foreign currency translation	(118)		12		(1)

Total included in other comprehensive loss (before tax effect)	(783)		(705)		(227)
Total recognized in net periodic benefit cost and included in other comprehensive loss	$	(441)	$	(428)	$	176

The Company uses significant judgment to determine the measurement of their non-U.S. defined benefit pension plans’ assets and liabilities. These amounts are calculated by an independent actuary. The present value of the defined benefit obligation depends on a number of factors that are determined on an actuarial basis using a number of assumptions. Any change in these assumptions will impact the present value of the defined benefit obligation.

The actuarial gains and losses recognized in the pension expense are determined using the so-called “10% corridor” method, i.e. actuarial gains and losses which exceed 10% of the higher of the plan assets and the projected benefit obligation are amortized on a straight line basis over the average remaining service period of the active plan participants. Any prior service costs are amortized on a straight line basis over the average remaining service period of the active plan participants.

The Company determines the appropriate discount rate at the end of each year. This is the interest rate that should be used to determine the present value of estimated future cash outflows expected to be required to settle the pension obligations. In determining the appropriate discount rate, the Company considers the interest rates of high-quality corporate bonds that are denominated in the currency in which the benefits will be paid, and that have terms to maturity approximating the terms of the related obligation. The other assumptions for pension obligations are based in part on market conditions.

Significant assumptions used in determining benefit obligations and net periodic benefit cost are as follows:


	Year ended December 31,
	2023		2022		2021
Defined benefit obligations:
Discount rate	3.25	%	3.80	%	0.90	%
Rate of salary increase	2.70	%	4.67	%	4.27	%
Inflation	1.80	%	2.30	%	1.80	%

Defined benefit cost:
Discount rate	3.25	%	3.80	%	0.90	%
Rate of salary increase	2.70	%	4.67	%	4.27	%
Rate of return on plan assets	1.80	%	1.20	%	0.90	%
Inflation	1.80	%	2.30	%	1.80	%

Plan Assets

The Company’s non-U.S. defined benefit plans are insured by a third party. The investments are governed by the insurer, who oversees all investment decisions. The insurance contracts are classified as Level 2 because a portion of the underlying funds are valued using significant other observable inputs. The insurance contracts provide for a guaranteed interest credit and a profit-sharing adjustment based on the actual performance of the underlying investment assets of the insurer. The fair value of the contract is determined by the insurer based on the premiums paid by the Company plus interest credits plus the profit-sharing adjustment less benefit payments.

The major categories of plan assets are as follows:


	As of December 31,
	2023		2022

	(In thousands)
Assets held by:
Insurance companies (collective and individual)	$	3,607	$	3,181

Expected Cash Flows

The Company expects to contribute $0.4 million to its non-U.S. defined benefit pension plans during 2024.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480482/715-20-55-17

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//715/tableOfContent

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (p)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480126/715-20-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480266/715-60-50-3

+ Details

Goodwill and Intangible Assets - Future Estimated Amortization Expense (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2024	$ 17,625
2025	17,625
2026	17,625
2027	17,625
2028	17,625
Thereafter	78,165
Net Carrying Value	$ 166,290

Cover - USD ($) $ in Millions	12 Months Ended
Cover - USD ($) $ in Millions	Dec. 31, 2023	Feb. 23, 2024	Jun. 30, 2023
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-38285
Entity Registrant Name	BANDWIDTH INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	56-2242657
Entity Address, Address Line One	2230 Bandmate Way
Entity Address, City or Town	Raleigh
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27607
City Area Code	(800)
Local Phone Number	808-5150
Title of 12(b) Security	Class A Common Stock, par value $0.001 per share
Trading Symbol	BAND
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction	false
Entity Shell Company	false
Entity Public Float			$ 313.7
Documents Incorporated by Reference	Portions of the registrant’s Definitive Proxy Statement for the 2024 Annual Meeting of Stockholders are incorporated herein by reference in Part II and Part III of this Annual Report on Form 10-K to the extent stated herein. Such Definitive Proxy Statement will be filed with the Securities and Exchange Commission within 120 days of the registrant’s fiscal year ended December 31, 2023.
Entity Central Index Key	0001514416
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
Class A voting common stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		24,312,661
Class B voting common stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		1,958,028

Goodwill and Intangible Assets - Summary of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Roll Forward]
Beginning balance	$ 326,405	$ 344,423
Foreign currency translation adjustments	9,467	(18,018)
Ending balance	$ 335,872	$ 326,405

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References + Details

Debt - 2026 Convertible Notes (Details)	1 Months Ended			12 Months Ended
Debt - 2026 Convertible Notes (Details)	Mar. 31, 2023 USD ($)	Nov. 30, 2022 USD ($)	Feb. 28, 2020 USD ($) $ / shares	Dec. 31, 2023 USD ($) $ / shares	Dec. 31, 2022 USD ($) $ / shares	Dec. 31, 2021 USD ($) $ / shares	Mar. 31, 2021 $ / shares
Debt Instrument [Line Items]
Net gain on extinguishment of debt				$ 12,767,000	$ 40,205,000	$ 0
Class A voting common stock
Debt Instrument [Line Items]
Common stock, par value (in usd per share) \| $ / shares			$ 0.001	$ 0.001	$ 0.001		$ 0.001
2026 Convertible Notes:
Debt Instrument [Line Items]
Cash redemption price (as a percent)				100.00%
2026 Convertible Notes: \| Convertible notes
Debt Instrument [Line Items]
Principal amount	$ 175,000,000		$ 400,000,000	$ 175,000,000	$ 240,000,000
Stated rate (as a percent)			0.25%
Total net proceeds			$ 344,700,000
Effective interest rate (as a percent)			0.509%
Conversion price (in usd per share) \| $ / shares			$ 91.03			$ 91.03
Repurchased face amount	65,000,000	$ 160,000,000
Repayments of debt	$ 51,300,000	$ 117,200,000
Net gain on extinguishment of debt				$ 12,800,000	$ 40,200,000
2026 Convertible Notes: \| Convertible notes \| Class A voting common stock
Debt Instrument [Line Items]
Conversion ratio			0.0109857	0.0109857	0.0109857

Summary of Significant Accounting Policies - Accounts Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Allowance for doubtful accounts	$ 1,128	$ 1,191
Unbilled accounts receivable	$ 43,631	$ 33,863

Stock-Based Compensation - Additional Information (Details) - USD ($)					12 Months Ended
	May 18, 2023	Jan. 01, 2022	Jan. 01, 2018	Nov. 09, 2017	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)					7,494,255	4,646,215
Aggregate intrinsic value of stock options exercised					$ 400,000	$ 600,000	$ 9,300,000
Granted (in shares)					0
Unrecognized cost for stock based compensation					$ 0
Stock Option Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)				0
A2017 Equity Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)				1,050,000
Common stock capital shares reserved for future issuance percent increase			5.00%
Increase in shares available for grant (in shares)	2,500,000	1,168,950
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)					5,066,159	2,607,106
Unrecognized compensation cost related to non-vested RSUs					$ 79,400,000
Unrecognized cost for stock based compensation, period for recognition (in years)					2 years 4 months 6 days
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)					97,480	159,741
Options \| A2017 Equity Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual life				10 years

Employee Benefit Plans - Significant Pension Benefit Costs Assumptions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined benefit obligations:
Discount rate	3.25%	3.80%	0.90%
Rate of salary increase	2.70%	4.67%	4.27%
Inflation	1.80%	2.30%	1.80%
Defined benefit cost:
Discount rate	3.25%	3.80%	0.90%
Rate of salary increase	2.70%	4.67%	4.27%
Inflation	1.80%	2.30%	1.80%
Non-U.S. \| Pension Plan
Defined benefit cost:
Rate of return on plan assets	1.80%	1.20%	0.90%

Leases (Tables)

12 Months Ended

Dec. 31, 2023

Leases [Abstract]

Components of Lease Expense and Supplemental Cash Flow and Other Information

The components of lease expense recorded in the consolidated statements of operations were as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
Operating lease cost		$	15,655	$	7,750	$	6,818





Sublease income		—		(206)		(384)
Total net lease cost		$	15,655	$	7,544	$	6,434

Other supplemental information related to operating leases were as follows:


	Year ended December 31,
		2023		2022		2021








Weighted average remaining lease term (in years)		19.30		2.12		2.95



Weighted average discount rate		8.76	%	4.58	%	4.78	%

Schedule of Maturities of Operating Lease Liabilities

Maturities of operating lease liabilities were as follows:


	As of December 31,
	2023


	(In thousands)


2024	$	23,313
2025	22,277
2026	21,722
2027	22,122
2028	22,462
Thereafter	378,808
Total lease payments	490,704
Less: imputed interest	(264,693)

Total lease obligations	226,011
Less: current obligations	(5,463)
Long-term lease obligations	$	220,548

Basic and Diluted (Loss) Income per Common Share (Tables)

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

The components of basic and diluted (loss) income per share are as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands, except share and per share amounts)
Earnings per share


Net (loss) income attributable to common stockholders		$	(16,343)	$	19,570	$	(27,362)
Net (loss) income per share:
Basic		$	(0.64)	$	0.77	$	(1.09)
Diluted		$	(0.64)	$	(0.48)	$	(1.09)
Numerator used to compute net (loss) income per share:
Basic		$	(16,343)	$	19,570	$	(27,362)
Net gain on extinguishment of debt, net of taxes		—		(39,614)		—
Interest expense on convertible notes, net of taxes		—		5,147		—
Diluted (1)		$	(16,343)	$	(14,897)	$	(27,362)














Weighted average number of common shares outstanding:
Basic		25,612,724		25,282,796		25,090,916

Convertible debt conversion		—		5,625,073		—



Diluted		25,612,724		30,907,869		25,090,916

________________________

Schedule of Anti-dilutive Common Shares Excluded from Calculation of Net Loss

The following common share equivalents were excluded from the weighted average shares used to calculate net (loss) income per common share because their effects would have been anti-dilutive:


	As of December 31,
	2023	2022	2021
Stock options issued and outstanding	97,480	159,741	180,209
Restricted stock units issued and outstanding	5,911,794	2,607,106	344,486
Convertible senior notes (1) (2)	3,442,229	—	987,149
Total	9,451,503	2,766,847	1,511,844

________________________

Summary of Significant Accounting Policies - Advertising Costs (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) segment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Advertising costs	$ 1,200	$ 1,500	$ 1,800
Number of operating segments \| segment	1
Gain on business interruption insurance recoveries	$ 4,000	$ 0	$ 0
Restricted Stock Units, Non-Employee
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Service period	1 year
Minimum \| Stock Options And Restricted Stock Units, Employees
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Service period	3 years
Maximum \| Stock Options And Restricted Stock Units, Employees
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Service period	4 years

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Geographic Information (Tables)

12 Months Ended

Dec. 31, 2023

Segment Reporting [Abstract]

Schedule of Revenue by Geographical Area

The Company generates its revenue primarily in North America. Revenue by geographic area is detailed in the table below, which is apportioned based on the destination of the service:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
North America		$	514,048	$	484,105	$	433,463
Rest of World		87,069		89,047		57,444
Total		$	601,117	$	573,152	$	490,907

Fair Value Measurements - Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 131,987	$ 113,641	$ 331,453
Amortized cost or carrying value	21,422	70,917
Unrealized gains	66	426
Unrealized losses	0	(112)
Total marketable securities	21,488
Total financial assets	142,146	135,899
Money market account
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	120,724	36,728
Time deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost or carrying value	20,000	6,645
Unrealized gains	0	0
Unrealized losses	0	(15)
U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost or carrying value		14,718
Unrealized gains		74
Unrealized losses		0
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost or carrying value		23,412
Unrealized gains		0
Unrealized losses		(97)
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		28,254
Amortized cost or carrying value	1,422	26,142
Unrealized gains	66	352
Unrealized losses	0	0
Total included in cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	120,724	64,982
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities	21,488	71,231
Total financial assets	142,212	136,213
Recurring \| Money market account
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	120,724	36,728
Recurring \| Time deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities	20,000	6,630
Recurring \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities		14,792
Recurring \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities		23,315
Recurring \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		28,254
Total marketable securities	1,488	26,494
Recurring \| Total included in cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	120,724	64,982
Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities	21,488	47,916
Total financial assets	142,212	112,898
Recurring \| Level 1 \| Money market account
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	120,724	36,728
Recurring \| Level 1 \| Time deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities	20,000	6,630
Recurring \| Level 1 \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities		14,792
Recurring \| Level 1 \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities		0
Recurring \| Level 1 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		28,254
Total marketable securities	1,488	26,494
Recurring \| Level 1 \| Total included in cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	120,724	64,982
Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities	0	23,315
Total financial assets	0	23,315
Recurring \| Level 2 \| Money market account
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Recurring \| Level 2 \| Time deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities	0	0
Recurring \| Level 2 \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities		0
Recurring \| Level 2 \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities		23,315
Recurring \| Level 2 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		0
Total marketable securities	0	0
Recurring \| Level 2 \| Total included in cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities	0	0
Total financial assets	0	0
Recurring \| Level 3 \| Money market account
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Recurring \| Level 3 \| Time deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities	0	0
Recurring \| Level 3 \| U.S. treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities		0
Recurring \| Level 3 \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total marketable securities		0
Recurring \| Level 3 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		0
Total marketable securities	0	0
Recurring \| Level 3 \| Total included in cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 0	$ 0

Property, Plant and Equipment - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Total cost	$ 255,802	$ 171,798
Less—accumulated depreciation	(77,938)	(72,045)
Total property, plant and equipment, net	177,864	99,753
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total cost	$ 16,036	16,494
Furniture and fixtures \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	5 years
Computer and office equipment
Property, Plant and Equipment [Line Items]
Total cost	$ 13,669	14,160
Computer and office equipment \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	5 years
Computer and office equipment \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	2 years
Telecommunications equipment
Property, Plant and Equipment [Line Items]
Total cost	$ 82,991	80,251
Telecommunications equipment \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	7 years
Telecommunications equipment \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	5 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total cost	$ 75,437	6,410
Leasehold improvements \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	15 years
Leasehold improvements \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	5 years
Software
Property, Plant and Equipment [Line Items]
Total cost	$ 12,552	7,051
Property and equipment, useful life	3 years
Internal-use software development
Property, Plant and Equipment [Line Items]
Total cost	$ 25,909	23,677
Internal-use software development \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	4 years
Automobile
Property, Plant and Equipment [Line Items]
Total cost	$ 507	665
Property and equipment, useful life	3 years
Land
Property, Plant and Equipment [Line Items]
Total cost	$ 27,771	23,090
Land Improvements
Property, Plant and Equipment [Line Items]
Total cost	$ 930	$ 0
Property and equipment, useful life	20 years

Geographic Information

12 Months Ended

Dec. 31, 2023

Segment Reporting [Abstract]

Geographic Information

9. Geographic Information

The Company generates its revenue primarily in North America. Revenue by geographic area is detailed in the table below, which is apportioned based on the destination of the service:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
North America		$	514,048	$	484,105	$	433,463
Rest of World		87,069		89,047		57,444
Total		$	601,117	$	573,152	$	490,907

During the three months ended March 31, 2023, the Company changed its methodology for apportioning the revenue by geographic area, from basing the revenue on the customer billing address to basing the revenue on the destination of the service, in order to provide a more transparent metric and to be consistent with other information provided publicly. Accordingly, 2023 and 2022 have been conformed to the updated methodology, however due to data limitations, 2021 is presented under the previous methodology.

The Company’s long-lived assets were primarily held in North America as of December 31, 2023 and 2022. As of December 31, 2023 and 2022, long-lived assets held outside of North America were $4.5 million and $9.1 million, respectively.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-15

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-40

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//280/tableOfContent

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-26

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-34

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-41

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

+ Details

Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Schedule of Property, Plant and Equipment, Net

Property, plant and equipment, net consisted of the following:



	As of December 31,				Useful Life
	2023		2022

	(In thousands)				(In years)
Furniture and fixtures	$	16,036	$	16,494	5
Computer and office equipment	13,669		14,160		2 to 5
Telecommunications equipment	82,991		80,251		5 to 7
Leasehold improvements	75,437		6,410		5 to 15
Software	12,552		7,051		3
Internal-use software development	25,909		23,677		4
Automobile	507		665		3
Land	27,771		23,090		Indefinite
Land Improvements	930		—		20
Total cost	255,802		171,798
Less—accumulated depreciation	(77,938)		(72,045)
Total property, plant and equipment, net	$	177,864	$	99,753

Schedule of Depreciation Expense

The Company recognized depreciation expense, which includes amortization of capitalized software development costs, as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
Cost of revenue		$	16,273	$	13,602	$	12,606
Research and development		3,977		2,311		2,166
Sales and marketing		2,628		1,331		1,090
General and administrative		1,565		1,175		1,661
Total depreciation expense		$	24,443	$	18,419	$	17,523

Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Operating lease cost	$ 15,655	$ 7,750	$ 6,818
Sublease income	0	(206)	(384)
Total net lease cost	$ 15,655	$ 7,544	$ 6,434

Stock-Based Compensation - Restricted Stock Unit Activity (Details) - RSUs - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Number of awards outstanding
Beginning balance (in shares)	2,607,106
Granted (in shares)	3,431,074
Vested (in shares)	(804,962)
Forfeited or cancelled (in shares)	(167,059)
Ending balance (in shares)	5,066,159	2,607,106
Weighted-average grant date fair value (Per share)
Beginning balance (in usd per share)	$ 32.33
Granted (in usd per share)	11.35	$ 30.43	$ 143.31
Vested (in usd per share)	31.29
Forfeited or cancelled (in usd per share)	28.77
Ending balance (in usd per share)	$ 18.41	$ 32.33
Total fair value of RSUs vested (in thousands)	$ 25,186	$ 15,038	$ 12,571

Property, Plant and Equipment

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

6. Property, Plant and Equipment

Property, plant and equipment, net consisted of the following:



	As of December 31,				Useful Life
	2023		2022

	(In thousands)				(In years)
Furniture and fixtures	$	16,036	$	16,494	5
Computer and office equipment	13,669		14,160		2 to 5
Telecommunications equipment	82,991		80,251		5 to 7
Leasehold improvements	75,437		6,410		5 to 15
Software	12,552		7,051		3
Internal-use software development	25,909		23,677		4
Automobile	507		665		3
Land	27,771		23,090		Indefinite
Land Improvements	930		—		20
Total cost	255,802		171,798
Less—accumulated depreciation	(77,938)		(72,045)
Total property, plant and equipment, net	$	177,864	$	99,753

The Company capitalizes the costs to design software for internal use related to the development of its platform during the application development stage of the projects. The costs are primarily comprised of salaries and benefits of the projects’ engineers and product development teams. Internally developed software is reported at cost less accumulated amortization. Amortization begins once the project is substantially complete and ready for its intended use. Costs incurred prior to the application development stage, maintenance activities or minor upgrades are expensed in the period incurred. Unamortized software development costs were approximately $15.3 million and $8.4 million as of December 31, 2023 and 2022, respectively.

The Company capitalized $10.6 million, $3.8 million, and $3.9 million of software development costs for the years ended December 31, 2023, 2022 and 2021, respectively.

Amortization expense related to capitalized software development costs was $3.2 million, $2.2 million, and $1.8 million for the years ended December 31, 2023, 2022 and 2021, respectively. As of December 31, 2023, unamortized implementation costs related to cloud computing arrangements were $0.1 million, which is included in prepaid expenses and other current assets.

The Company leases automobiles under leases accounted for as finance leases, which expire on various dates between 2024 and 2026. As of December 31, 2023, cost and accumulated depreciation of the assets under finance leases recorded by the Company were $0.5 million and $0.3 million, respectively. As of December 31, 2022, cost and accumulated depreciation of the assets under finance leases recorded by the Company were $0.7 million and $0.3 million, respectively.

The Company recognized an impairment of $0.5 million during each of the years ended December 31, 2023, 2022 and 2021, related to capitalized software development costs that provided no future benefit and therefore were impaired. This expense is reflected within other income (expense), net as of December 31, 2023 and 2022 and cost of revenue as of December 31, 2021 in the accompanying consolidated statements of operations.

The Company recognized depreciation expense, which includes amortization of capitalized software development costs, as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
Cost of revenue		$	16,273	$	13,602	$	12,606
Research and development		3,977		2,311		2,166
Sales and marketing		2,628		1,331		1,090
General and administrative		1,565		1,175		1,661
Total depreciation expense		$	24,443	$	18,419	$	17,523

Debt - Interest Income and Interest Expense Disclosure (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Total interest expense	$ 3,719	$ 5,224
2026 Convertible Notes:
Debt Instrument [Line Items]
Contractual interest expense	465	997
Amortization of debt issuance costs	940	1,915
Total interest expense	1,405	2,912
2028 Convertible Notes:
Debt Instrument [Line Items]
Contractual interest expense	1,250	1,250
Amortization of debt issuance costs	1,064	1,062
Total interest expense	$ 2,314	$ 2,312

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Leases - Schedule of Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Operating Leases
2024	$ 23,313
2025	22,277
2026	21,722
2027	22,122
2028	22,462
Thereafter	378,808
Total lease payments	490,704
Less: imputed interest	(264,693)
Total lease obligations	226,011
Less: current obligations	(5,463)	$ (7,450)
Long-term lease obligations	$ 220,548	$ 4,640

Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2023

Retirement Benefits [Abstract]

Schedule of Projected Benefit Obligation and Plan Assets Changes

The following table summarizes information for the pension plans:


	As of December 31,
	2023		2022

	(In thousands)
Change in benefit obligation:
Benefit obligation at beginning of year	$	3,502	$	3,874
Service cost	264		268
Interest cost	146		35
Actuarial loss (gain)	13		(418)
Benefits paid	(41)		—
Taxes, insurance premiums and administrative expenses	(61)		(50)

Impact of foreign currency translation	104		(207)
Benefit obligation at end of year	$	3,927	$	3,502

Change in plan assets:
Fair value of plan assets at beginning of year	$	3,181	$	2,958
Return on plan assets	41		26
Actuarial gain	—		72
Employer contribution	393		332

Benefits paid	(41)		—
Taxes, insurance premiums and administrative expenses	(61)		(50)
Impact of foreign currency translation	94		(157)
Fair value of plan assets at end of year	3,607		3,181
Funded status, net liability	$	320	$	321

Schedule of Defined Benefit Plan With Accumulated Benefit Obligation in Excess of Plan Assets

The following table summarizes information for the Company’s pension plans with an accumulated benefit obligation in excess of plan assets:


	As of December 31,
	2023		2022

	(In thousands)
Projected benefit obligation	$	3,927	$	3,502
Accumulated benefit obligation	3,623		3,265
Fair value of plan assets	3,607		3,181

Schedule of Accumulated Benefit Obligation in Excess of Plan Assets

Pretax amounts for net periodic benefit cost and other amounts for the defined benefit pension plans consisted of the following components:


	Year ended December 31,
	2023		2022		2021

	(In thousands)
Service cost	$	264	$	268	$	396
Interest cost	146		35		21
Return on plan assets	(41)		(26)		(14)
Amortization of actuarial gain	(27)		—		—
Net periodic pension cost	342		277		403
Changes in plan assets and benefit obligations included in other comprehensive loss:
Unrecognized net actuarial (gain) loss beginning of year	(705)		(227)		17
Actuarial gain recognized during year	27		—		—
Actuarial loss (gain) on benefit obligation	13		(418)		(237)
Actuarial gain on fair value of plan assets	—		(72)		(6)
Impact of foreign currency translation	(118)		12		(1)

Total included in other comprehensive loss (before tax effect)	(783)		(705)		(227)
Total recognized in net periodic benefit cost and included in other comprehensive loss	$	(441)	$	(428)	$	176

Schedule Significant Pension Benefit Costs Assumptions

Significant assumptions used in determining benefit obligations and net periodic benefit cost are as follows:


	Year ended December 31,
	2023		2022		2021
Defined benefit obligations:
Discount rate	3.25	%	3.80	%	0.90	%
Rate of salary increase	2.70	%	4.67	%	4.27	%
Inflation	1.80	%	2.30	%	1.80	%

Defined benefit cost:
Discount rate	3.25	%	3.80	%	0.90	%
Rate of salary increase	2.70	%	4.67	%	4.27	%
Rate of return on plan assets	1.80	%	1.20	%	0.90	%
Inflation	1.80	%	2.30	%	1.80	%

Schedule of Major Categories of Plan Assets

The major categories of plan assets are as follows:


	As of December 31,
	2023		2022

	(In thousands)
Assets held by:
Insurance companies (collective and individual)	$	3,607	$	3,181

Income Taxes - Summary of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning balance	$ 4,800	$ 3,062
Gross increases—tax positions in prior period	142	613
Gross increases—tax positions in current period	1,228	1,125
Unrecognized tax benefits, ending balance	$ 6,170	$ 4,800

Summary of Significant Accounting Policies - Goodwill (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) reporting_unit	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Goodwill [Line Items]
Capitalized contract cost, amortization period	4 years
Reporting units \| reporting_unit	1
Goodwill impairment charges \| $	$ 0	$ 0	$ 0
Internal-use software development
Goodwill [Line Items]
Capitalized contract cost, amortization period	4 years

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Schedule of Domestic and Foreign Components of Income (Loss)

The following table presents domestic and foreign components of (loss) income before income taxes for the tax years ended December 31, 2023, 2022 and 2021:


	Year Ended December 31,
	2023		2022		2021

	(In thousands)
United States	$	759	$	30,594	$	(27,547)
International	(20,062)		(13,288)		(3,648)
(Loss) income before income taxes	$	(19,303)	$	17,306	$	(31,195)

Schedule of (Provision) Benefit for Income Taxes from Continuing Operations

Benefit for income taxes from operations consists of the following:


	Year Ended December 31,

	2023		2022		2021

	(In thousands)
Current:
Federal	$	(653)	$	(2,717)	$	(2,713)
State	(1,309)		(803)		(145)
Foreign	(2,219)		(815)		(1,627)
Total	(4,181)		(4,335)		(4,485)
Deferred:
Federal	(75)		1,004		(364)
State	—		(1)		—
Foreign	7,216		5,596		8,682
Total	7,141		6,599		8,318
Income tax benefit	$	2,960	$	2,264	$	3,833

Schedule of Effective Income Tax Rate Reconciliation

The following table presents a reconciliation of the statutory federal tax rate and the Company’s effective tax rate for the years ended December 31, 2023, 2022 and 2021:


	Year Ended December 31,
	2023		2022		2021
Federal Tax Rate	21.0	%	21.0	%	21.0	%
State Tax Rate - statutory blended rate	4.3		4.3		4.2
Other effective state tax adjustments	(5.2)		3.6		(1.4)
Non-deductible expenses	(4.1)		4.0		(6.1)
Research tax benefits	24.4		(31.6)		7.9
Stock-based compensation	(18.0)		6.3		13.9
Change in valuation allowance	(11.7)		(16.1)		16.3
Deferred tax rate change	0.6		0.5		(0.2)
Voxbone US 338(g) gain	—		—		(8.9)
Intangibles and deferred adjustments	—		(4.7)		(40.2)
Foreign rate differential	2.8		1.6		1.3
Other	1.2		(2.0)		4.5
Total	15.3	%	(13.1)	%	12.3	%

Schedule of Significant Components of Deferred Tax Assets and Liabilities

The following table presents the significant components of the Company’s net deferred tax liability:


	As of December 31,
	2023		2022

	(In thousands)
Deferred tax assets:
Allowance for doubtful accounts	$	80	$	173
Accrued liabilities	3,459		4,370
Operating lease liabilities	57,152		3,456
Deferred revenue	1,915		1,949

Stock-based compensation	3,363		3,216

Capitalized research and development expenses	40,306		20,997
Accrued lease incentive	—		2,645
Tax credits	12,994		10,948
Net operating losses	17,421		25,691
Other deferred tax assets	3,238		4,592
Gross deferred tax assets	139,928		78,037
Less: valuation allowance	(67,950)		(65,678)
Total deferred tax assets	71,978		12,359
Deferred tax liabilities:
Property, plant and equipment	24,469		4,890
Goodwill	1,416		1,272
Intangibles	39,334		41,591
Operating lease assets	39,780		3,072


Total deferred tax liabilities	104,999		50,825
Net deferred tax liability	$	(33,021)	$	(38,466)

Schedule of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:


	Year Ended December 31,
	2023		2022

	(In thousands)
Unrecognized tax benefits—January 1,	$	4,800	$	3,062
Gross increases—tax positions in prior period	142		613

Gross increases—tax positions in current period	1,228		1,125


Unrecognized tax benefits—December 31,	$	6,170	$	4,800

Debt - Convertible Senior Notes and Capped Call Transactions (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 16, 2021	Feb. 28, 2020
Debt Instrument [Line Items]
Net costs incurred	$ 25,500	$ 43,320
Class A voting common stock
Debt Instrument [Line Items]
Class A common stock covered, subject to anti-dilution adjustments (in shares)	1,394,525	1,922,498
Convertible notes \| 2026 Convertible Notes
Debt Instrument [Line Items]
Initial conversion strike price (in usd per share)		$ 91.03
Initial cap price (in usd per share)		$ 137.40
Convertible notes \| 2028 Convertible Notes
Debt Instrument [Line Items]
Initial conversion strike price (in usd per share)	$ 179.27
Initial cap price (in usd per share)	$ 260.76

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Employee Benefit Plans - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Matching contributions	$ 4,800	$ 4,600	$ 3,800
Net actuarial loss (gain)	Other income (expense), net	Other income (expense), net
Non-U.S. \| Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	$ 400
Non-U.S. \| Pension Plan \| Other Liabilities
Defined Benefit Plan Disclosure [Line Items]
Pension liability	$ 300	$ 300

Goodwill and Intangible Assets - Additional Information (Details)	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Weighted average useful life	10 years 1 month 6 days

Financial Statement Components

12 Months Ended

Dec. 31, 2023

Financial Statement Components [Abstract]

Financial Statement Components

4. Financial Statement Components

Accounts receivable, net of allowances consist of the following:



	As of December 31,
	2023		2022

	(In thousands)
Trade accounts receivable	$	35,612	$	40,332
Unbilled accounts receivable	43,631		33,863
Allowance for doubtful accounts and reserve for expected credit losses	(1,128)		(1,191)
Other accounts receivable	40		1,461
Total accounts receivable, net	$	78,155	$	74,465

Components of allowance for doubtful accounts and reserve for expected credit losses are as follows:


	Year ended December 31,
		2023		2022

		(In thousands)
Balance, beginning of period		$	(1,191)	$	(1,661)
Charged to bad debt expense, net of reversals		(733)		(543)
Deductions (1)		807		983
Impact of foreign currency translation		(11)		30



Balance, end of period		$	(1,128)	$	(1,191)

________________________

(1) Write-off of uncollectible accounts after all collection efforts have been exhausted.

Accrued expenses and other current liabilities consisted of the following:



	As of December 31,
	2023		2022

	(In thousands)
Accrued expense	$	40,731	$	29,990
Accrued compensation and benefits	19,142		21,595
Accrued sales, use, VAT and telecommunications related taxes	8,467		7,799



Income tax payable	—		2,235
Other accrued expenses	674		958
Total accrued expenses and other current liabilities	$	69,014	$	62,577

Other liabilities consisted of the following:



	As of December 31,
	2023		2022

	(In thousands)
Lease incentive	$	—	$	10,468
Other liabilities	386		708
Total other liabilities	$	386	$	11,176

Employee Benefit Plans - Schedule of Major Categories of Plan Assets (Details) - Pension Plan - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value of plan assets	$ 3,600	$ 3,200
Non-U.S.
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value of plan assets	3,607	3,181	$ 2,958
Non-U.S. \| Insurance Companies
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value of plan assets	$ 3,607	$ 3,181

- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References + Details

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies Operating Leases The Company leases office space under non-cancelable operating lease agreements that expire on various dates through July 2043. As of December 31, 2023, the Company has $496.1 million in future minimum rent payments for its current office space. See Note 5, “Leases,” to the consolidated financial statements, for additional details on the Company’s operating lease commitments. Contractual Obligations As of December 31, 2023, the Company has $23.0 million in non-cancellable purchase obligations, consisting of primarily network equipment maintenance and software license contracts, of which $12.9 million will be fulfilled within one year. Legal Matters The Company is involved as a defendant in various litigation, including, but not limited to, lawsuits alleging that the Company failed to bill, collect and remit certain taxes and surcharges associated with the provision of 911 services pursuant to applicable laws in various jurisdictions. The Company intends to vigorously defend these lawsuits and believes that it has meritorious defenses to each. However, litigation is inherently uncertain, and any judgment or injunctive relief entered against the Company or any adverse settlement could adversely affect the Company’s business, results of operations and financial condition.

Income Taxes

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Income Taxes

14. Income Taxes

The following table presents domestic and foreign components of (loss) income before income taxes for the tax years ended December 31, 2023, 2022 and 2021:


	Year Ended December 31,
	2023		2022		2021

	(In thousands)
United States	$	759	$	30,594	$	(27,547)
International	(20,062)		(13,288)		(3,648)
(Loss) income before income taxes	$	(19,303)	$	17,306	$	(31,195)

Benefit for income taxes from operations consists of the following:


	Year Ended December 31,

	2023		2022		2021

	(In thousands)
Current:
Federal	$	(653)	$	(2,717)	$	(2,713)
State	(1,309)		(803)		(145)
Foreign	(2,219)		(815)		(1,627)
Total	(4,181)		(4,335)		(4,485)
Deferred:
Federal	(75)		1,004		(364)
State	—		(1)		—
Foreign	7,216		5,596		8,682
Total	7,141		6,599		8,318
Income tax benefit	$	2,960	$	2,264	$	3,833

The following table presents a reconciliation of the statutory federal tax rate and the Company’s effective tax rate for the years ended December 31, 2023, 2022 and 2021:


	Year Ended December 31,
	2023		2022		2021
Federal Tax Rate	21.0	%	21.0	%	21.0	%
State Tax Rate - statutory blended rate	4.3		4.3		4.2
Other effective state tax adjustments	(5.2)		3.6		(1.4)
Non-deductible expenses	(4.1)		4.0		(6.1)
Research tax benefits	24.4		(31.6)		7.9
Stock-based compensation	(18.0)		6.3		13.9
Change in valuation allowance	(11.7)		(16.1)		16.3
Deferred tax rate change	0.6		0.5		(0.2)
Voxbone US 338(g) gain	—		—		(8.9)
Intangibles and deferred adjustments	—		(4.7)		(40.2)
Foreign rate differential	2.8		1.6		1.3
Other	1.2		(2.0)		4.5
Total	15.3	%	(13.1)	%	12.3	%

For the year ended December 31, 2023, the Company recognized an income tax benefit of $3.0 million on pre-tax book loss of $19.3 million, resulting in an effective income tax rate of 15.3%. For the year ended December 31, 2022, the Company recognized an income tax benefit of $2.3 million on pre-tax book income of $17.3 million, resulting in an effective income tax rate of (13.1)%. For the year ended December 31, 2021, the Company recognized an income tax benefit of $3.8 million on pre-tax book loss of $31.2 million, resulting in an effective income tax rate of 12.3%.

In 2023, the Company’s valuation allowance in the U.S. continued to offset many of the permanent tax adjustments within the effective tax rate. These adjustments include state taxes, federal research tax credits under Internal Revenue Code Section 41, equity compensation in the U.S., and other non-deductible expenditures in the U.S. The Company has disclosed the statutory blended state income tax rate in the income tax rate reconciliation table. This statutory blended state income tax rate is the rate applied to the Company’s U.S. taxable earnings to calculate its state income tax liability. The Company has also disclosed other effective state tax adjustments which primarily include the state tax impact of permanent tax adjustments and the reconciling adjustment to remove the statutory blended state income tax rate effect from income or loss generated outside of the U.S. The Company continues to generate income tax benefits in the current period related to income tax credits recognized for qualified research activities in the U.S. The applicable federal tax law and regulations define qualified research activities as research and development activities conducted in the U.S. that involve a process of experimentation designed to discover new information intended to develop a new or improved business component. Absent the valuation allowance, equity compensation also impacts the effective tax rate to the extent the income tax deduction exceeds or is below the related book expense, as required under ASC 718-740-35-2. Other U.S. non-deductible expenses that are offset by the valuation allowance consist primarily of non-deductible executive compensation under Internal Revenue Code 162(m).

The following table presents the significant components of the Company’s net deferred tax liability:


	As of December 31,
	2023		2022

	(In thousands)
Deferred tax assets:
Allowance for doubtful accounts	$	80	$	173
Accrued liabilities	3,459		4,370
Operating lease liabilities	57,152		3,456
Deferred revenue	1,915		1,949

Stock-based compensation	3,363		3,216

Capitalized research and development expenses	40,306		20,997
Accrued lease incentive	—		2,645
Tax credits	12,994		10,948
Net operating losses	17,421		25,691
Other deferred tax assets	3,238		4,592
Gross deferred tax assets	139,928		78,037
Less: valuation allowance	(67,950)		(65,678)
Total deferred tax assets	71,978		12,359
Deferred tax liabilities:
Property, plant and equipment	24,469		4,890
Goodwill	1,416		1,272
Intangibles	39,334		41,591
Operating lease assets	39,780		3,072


Total deferred tax liabilities	104,999		50,825
Net deferred tax liability	$	(33,021)	$	(38,466)

The Company’s accounting for deferred taxes involves the evaluation of a number of factors concerning the realizability of its net deferred tax assets. The Company primarily considered its historic performance, the nature of its deferred tax assets and the timing, likelihood and amount, if any, of future taxable income during the periods in which those temporary differences and carryforwards become deductible. Based on an analysis of these factors, the Company determined that in 2023, a valuation allowance against U.S. deferred tax assets was required.

As of December 31, 2023, the Company had approximately $44.3 million in U.S. federal net operating loss carryforwards, $16.3 million in U.K. loss carryforwards, and $12.8 million in U.S. federal tax credits. All U.S. federal net operating loss carryforwards were generated after the enactment of the Tax Cuts and Jobs Act (the “Act”) and as such do not expire, but can only be utilized to offset up to 80% of taxable income in any given year. The U.S. federal tax credits begin to expire in 2039.

As of December 31, 2023, the Company had approximately $63.9 million in state net operating loss carryforwards. If not utilized, some state net operating loss carryforwards will expire at various dates beginning in 2026.

At December 31, 2023, the amount of unremitted earnings generated by the Company’s foreign subsidiaries was not significant. The Company does not assert indefinite reinvestment on a portion of its unremitted earnings of certain foreign subsidiaries as of December 31, 2023. On the earnings that are not indefinitely reinvested, the Company did not recognize deferred income taxes related to those unremitted foreign earnings, due to the tax favorable manner in which it would be repatriated. For the subsidiaries that the Company asserts permanent reinvestment, if repatriation were to occur, the Company would be required to accrue U.S. taxes, if any, and remit applicable withholding taxes as appropriate. A determination of the amount of the unrecognized deferred tax liability related to these undistributed earnings is not practicable due to the complexity and variety of assumptions necessary based on the manner in which the undistributed earnings would be repatriated.

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:


	Year Ended December 31,
	2023		2022

	(In thousands)
Unrecognized tax benefits—January 1,	$	4,800	$	3,062
Gross increases—tax positions in prior period	142		613

Gross increases—tax positions in current period	1,228		1,125


Unrecognized tax benefits—December 31,	$	6,170	$	4,800

If the $6.2 million of unrecognized tax benefit is recognized, it would not impact the effective tax rate due to the valuation allowance on the Company’s net U.S. deferred tax assets.

For the years ended December 31, 2023 and 2022, the Company recognized interest and penalties of $0.3 million related to income taxes within income tax expense.

The Company expects no material changes in the twelve months following December 31, 2023 in its uncertain tax positions.

The Company files U.S. federal income tax returns as well as income tax returns in many U.S. states and foreign jurisdictions. The tax years 2020 through 2022 remain open to examination by the major jurisdictions in which the Company is subject to tax.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Federal Tax Rate	21.00%	21.00%	21.00%
State Tax Rate - statutory blended rate	4.30%	4.30%	4.20%
Other effective state tax adjustments	(5.20%)	3.60%	(1.40%)
Non-deductible expenses	(4.10%)	4.00%	(6.10%)
Research tax benefits	24.40%	(31.60%)	7.90%
Stock-based compensation	(18.00%)	6.30%	13.90%
Change in valuation allowance	(11.70%)	(16.10%)	16.30%
Deferred tax rate change	0.60%	0.50%	(0.20%)
Voxbone US 338(g) gain	0.00%	0.00%	(8.90%)
Intangibles and deferred adjustments	0.00%	(4.70%)	(40.20%)
Foreign rate differential	2.80%	1.60%	1.30%
Other	1.20%	(2.00%)	4.50%
Total	15.30%	(13.10%)	12.30%

Debt - Schedule of Debt (Details) - Convertible notes - USD ($)	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2021	Feb. 28, 2020
Debt Instrument [Line Items]
Total net carrying amount	$ 418,526,000		$ 480,546,000
2026 Convertible Notes:
Debt Instrument [Line Items]
Principal	175,000,000	$ 175,000,000	240,000,000		$ 400,000,000
Unamortized debt issuance costs	(1,891,000)		(3,805,000)
Total net carrying amount	173,109,000		236,195,000
2028 Convertible Notes:
Debt Instrument [Line Items]
Principal	250,000,000		250,000,000	$ 250,000,000
Unamortized debt issuance costs	(4,583,000)		(5,649,000)
Total net carrying amount	$ 245,417,000		$ 244,351,000

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Stockholders' Equity - Reserved Shares of Common Stock for Issuance (Details) - shares	Dec. 31, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	7,494,255	4,646,215
Stock options issued and outstanding
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	97,480	159,741
Nonvested restricted stock units issued and outstanding
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	5,066,159	2,607,106
Stock-based awards available for grant under the 2017 Plan
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	2,330,616	1,879,368

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 272
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483014/272-10-45-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 272
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482987/272-10-50-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(d))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(27)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(i)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(i)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(i)(2)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(i)(2)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3

+ Details

Summary of Significant Accounting Policies - Schedule of Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Receivables	$ 78,155	$ 74,465
Contract liabilities	$ 16,465	$ 15,487

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The consolidated financial statements and accompanying notes were prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”).

Reclassification

Principles of Consolidation

The consolidated financial statements include the accounts of Bandwidth Inc. and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

Use of Estimates

Revenue Recognition

Revenue recognition commences upon transfer of control of promised goods or services to customers in an amount that the Company expects to receive in exchange for those products or services.

The Company determines revenue recognition through the following steps:

•identification of the contract, or contracts, with a customer;

•identification of the performance obligations in the contract;

•determination of the transaction price;

•allocation of the transaction price to the performance obligations in the contract; and

•recognition of revenue, when, or as, the Company satisfies a performance obligation.

Nature of Products and Services

Revenue consists primarily of two categories: (1) cloud communications and (2) messaging surcharges, which are described and quantified below.


	Year ended December 31,
	2023		2022		2021

	(In thousands)

Cloud communications	$	478,892	$	474,576	$	449,656
Messaging surcharges	122,225		98,576		41,251
Total revenue	$	601,117	$	573,152	$	490,907

Cloud Communications

Messaging surcharges

Contract Assets and Liabilities

The following table provides information about receivables and contract liabilities from contracts with customers:


	As of December 31,
	2023		2022

	(In thousands)
Receivables (1)	$	78,155	$	74,465
Contract liabilities (2)	16,465		15,487

________________________

(1) Included in accounts receivable, net of allowance for doubtful accounts on the consolidated balance sheets.

(2) Included in current portion of deferred revenue and deferred revenue, net of current portion on the consolidated balance sheets.

Cost of Revenue

Fees paid to other network service providers arise when the Company purchases services such as minutes of use, phone numbers, messages, porting of customer numbers and network circuits.

Operating Expenses

Research and Development

Sales and Marketing

General and Administrative

Cash and Cash Equivalents

Marketable Securities

method and records such gains and losses in other income (expense), net on the consolidated statements of operations.

Accounts Receivable and Current Expected Credit Losses

Concentration of Credit Risk

With regard to customers, credit evaluation and account monitoring procedures are used to minimize the risk of loss. The Company believes that no additional credit risk beyond amounts provided for by the allowance for doubtful accounts are inherent in accounts receivable. As of December 31, 2023 and 2022, no individual customer represented more than 10% of the Company’s accounts receivable, net of allowance for doubtful accounts.

For the years ended December 31, 2023, 2022 and 2021, no individual customer represented more than 10% of the Company’s revenue.

Property, Plant and Equipment, net

Property, plant and equipment, net is stated at cost, less accumulated depreciation and amortization. Depreciation and amortization is calculated on a straight-line basis over the estimated useful lives of those assets. Refer to Note 6, “Property, Plant and Equipment” to these consolidated financial statements, for the useful lives of the Company’s property, plant and equipment as of December 31, 2023 and 2022.

Deferred Costs

Internal-Use Software Development Costs

Debt Issuance Costs

Amortization of Intangibles

Goodwill

The Company establishes its reporting units based on its current organizational structure and management’s view of the business. The Company has determined it has one reporting unit.

As of December 31, 2023, the Company completed a quantitative assessment under ASC 350 and determined that there was not an impairment of goodwill.

No goodwill impairment charges were recorded for the years ended December 31, 2023, 2022 and 2021.

Impairment of Long-Lived Assets

Business Combinations

Advertising Costs

The Company expenses advertising costs as incurred. Advertising costs totaled $1.2 million, $1.5 million and $1.8 million for the years ended December 31, 2023, 2022 and 2021, respectively, which are included in sales and marketing expenses in the accompanying consolidated statements of operations.

Commissions

Stock-Based Compensation

Income Taxes

Operating Segments

Earnings per Share

Foreign currency translation

The Company has foreign operations with non-USD functional currencies. The Euro and British Pound are the primary functional currencies for the Company’s international operations.

gains and losses are recognized in current period earnings as incurred, and included in other income (expense), net in the Company’s consolidated statements of operations.

Fair Value of Financial Instruments

•Level 1. Observable inputs based on unadjusted quoted prices in active markets for identical assets or liabilities;

•Level 2. Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and

•Level 3. Unobservable inputs for which there is little or no market data, which requires the Company to develop its own assumptions.

A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

Comprehensive Loss

Business Interruption Insurance Recovery

Beginning in September 2021, the Company’s communications network was subjected to a distributed denial of service attack (the “DDoS Attack”) that caused intermittent communications services disruptions affecting certain of its markets and customers. During the period of the DDoS Attack, the Company maintained certain insurance coverage, including business interruption insurance, intended to cover such circumstances. In June 2023, the Company resolved its claim with an insurer, pursuant to which the Company was entitled to receive $4.0 million in proceeds from business interruption insurance. The proceeds of the insurance payment were received in full in July 2023 and were recorded within gain on business interruption insurance recoveries on the Company’s consolidated statements of operations in the year ended December 31, 2023.

Recent Accounting Pronouncements Not Yet Adopted

Financial Statement Components - Allowance For Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	$ (1,191)	$ (1,661)
Charged to bad debt expense, net of reversals	(733)	(543)
Deductions	807	983
Impact of foreign currency translation	(11)	30
Balance, end of period	$ (1,128)	$ (1,191)

Debt (Tables)

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Schedule of Net Carrying Amount of Liability and Equity Component of Notes

The net carrying amount of the liability components of the Convertible Notes were as follows:



	As of December 31,
	2023		2022

2026 Convertible Notes:	(In thousands)
Principal	$	175,000	$	240,000

Unamortized debt issuance costs	(1,891)		(3,805)
2026 Convertible Notes net carrying amount	173,109		236,195

2028 Convertible Notes:
Principal	250,000		250,000

Unamortized debt issuance costs	(4,583)		(5,649)
2028 Convertible Notes net carrying amount	245,417		244,351
Total net carrying amount	$	418,526	$	480,546

Schedule of Interest Income and Interest Expense Disclosure

The following table sets forth the interest expense recognized related to the Convertible Notes:


	Year ended December 31,
		2023		2022

2026 Convertible Notes:		(In thousands)
Contractual interest expense		$	465	$	997

Amortization of debt issuance costs		940		1,915
Total interest expense related to the 2026 Convertible Notes		1,405		2,912

2028 Convertible Notes:
Contractual interest expense		1,250		1,250

Amortization of debt issuance costs		1,064		1,062
Total interest expense related to the 2028 Convertible Notes		2,314		2,312
Total interest expense		$	3,719	$	5,224

Schedule of Capped Call Transactions

The following table sets forth key terms and costs incurred for the Capped Calls related to the Convertible Notes as of December 31, 2023:


	2026 Convertible Notes		2028 Convertible Notes

	(In thousands, except share and per share amounts)
Initial approximate strike price per share, subject to certain adjustments	$	91.03	$	179.27
Initial cap price per share, subject to certain adjustments	$	137.40	$	260.76
Net costs incurred	$	43,320	$	25,500
Class A common stock covered, subject to anti-dilution adjustments	1,922,498		1,394,525

Property, Plant and Equipment - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Unamortized software development costs	$ 15.3	$ 8.4
Capitalized software development costs, additions	10.6	3.8	$ 3.9
Amortization of capitalized software development costs	3.2	2.2	1.8
Capitalized implementation costs related to cloud computing arrangements	0.1
Cost of assets under finance leases	0.5	0.7
Accumulated depreciation of assets under finance leases	0.3	0.3
Capitalized software impairments	$ 0.5	$ 0.5	$ 0.5

Employee Benefit Plans - Summary of Accumulated Benefit Obligation in Excess of Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Changes in plan assets and benefit obligations included in other comprehensive loss:
Unrecognized net actuarial (gain) loss beginning of year	$ (705)	$ (227)	$ 17
Actuarial gain recognized during year	27	0	0
Actuarial loss (gain) on benefit obligation	(13)	418	237
Actuarial gain on fair value of plan assets	0	(72)	(6)
Impact of foreign currency translation	(118)	12	(1)
Non-U.S. \| Pension Plan
Defined Benefit Plan, Plan Assets, Category [Line Items]
Service cost	264	268	396
Interest cost	146	35	21
Return on plan assets	(41)	(26)	(14)
Amortization of actuarial gain	(27)	0	0
Net periodic pension cost	342	277	403
Changes in plan assets and benefit obligations included in other comprehensive loss:
Actuarial gain recognized during year	0	(72)
Actuarial loss (gain) on benefit obligation	(13)	418
Impact of foreign currency translation	104	(207)
Total recognized in net periodic benefit cost and included in other comprehensive loss	(783)	(705)	(227)
Total recognized in net periodic benefit cost and included in other comprehensive loss	$ (441)	$ (428)	$ 176

Stock-Based Compensation

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

11. Stock-Based Compensation

Equity Incentive Plans

The Company adopted the 2010 Equity Compensation Plan (the “2010 Plan”) on July 26, 2010. On November 9, 2017, the 2010 Plan was terminated in connection with the Company’s initial public offering. Accordingly, no shares are available for future issuance under the 2010 Plan. However, the 2010 Plan continues to govern the terms and conditions of the outstanding awards granted thereunder.

The Company’s Second Amended and Restated 2017 Incentive Award Plan (as amended from time to time, the “2017 Plan”) became effective on November 9, 2017. The 2017 Plan provides for the grant of stock options, including incentive stock options and non-qualified stock options, stock appreciation rights, restricted stock, dividend equivalents, restricted stock units, and other stock or cash-based awards to employees, consultants and directors of the Company. A total of 1,050,000 shares of the Company’s Class A common stock were originally reserved for issuance under the 2017 Plan. These available shares automatically increase each January 1, beginning on January 1, 2018, by 5% of the number of shares of the Company’s Class A common stock outstanding on the final day of the immediately preceding calendar year. On January 1, 2023, the shares available for grant under the 2017 Plan were automatically increased by 1,168,950 shares. On May 18, 2023, stockholders approved an amendment to the 2017 Plan that increased the number of shares available for grant by 2,500,000 shares.

The terms of the stock option grants are determined by the Company’s Board of Directors. The Company’s stock options vest based on terms of the stock option agreements. The stock options have a contractual life of ten years.

Restricted stock units (“RSUs”) granted to employees, non-employee members of the Board of Directors and other Service Providers (as defined in the 2017 Plan) under the 2017 Plan are subject to an immediate or time-based vesting condition as specified by the underlying compensation plans. Vesting schedules may differ between different categories of award recipients. Stock compensation expense is based on the grant date fair value of the RSUs and is recognized on a ratable basis over the applicable service period. Depending on the nature of the

underlying compensation plan, certain share-based payment arrangements may be classified as liability-based awards resulting in classification as accrued expenses on the consolidated balance sheets with the corresponding offset to stock-based compensation expense.

As of December 31, 2023, awards granted under the 2010 Plan consisted of stock options and awards granted under the 2017 Plan consisted of stock options and RSUs.

Stock Options

The following summarizes the stock option activity for the year ended December 31, 2023:


	Number of options outstanding	Weighted- average exercise price (Per share)		Weighted- average remaining contract life (In years)	Aggregate intrinsic value (In thousands)
Outstanding as of December 31, 2022	159,741	$	10.42	2.57	$	2,001
Granted	—	—
Exercised	(61,349)	6.74
Forfeited or expired	(912)	9.46
Outstanding as of December 31, 2023	97,480	$	12.75	2.97	$	332

Options vested and exercisable at December 31, 2023	97,480	$	12.75	2.97	$	332
Options vested and expected to vest as of December 31, 2023	97,480	$	12.75	2.97	$	332

The total intrinsic value of stock options exercised for the years ended December 31, 2023, 2022 and 2021 was $0.4 million, $0.6 million and $9.3 million, respectively. Aggregate intrinsic value is computed based on the difference between the option exercise price and the fair value of the Company’s common stock at the time of such option exercises.

No options were granted for the year ended December 31, 2023.

As of December 31, 2021, all outstanding stock options were fully vested. As of December 31, 2023, the Company had no unrecognized compensation cost related to non-vested stock options.

Restricted Stock Units

The following summarizes the RSU activity for the year ended December 31, 2023:


	Number of awards outstanding	Weighted-average grant date fair value (Per share)
Nonvested RSUs as of December 31, 2022	2,607,106	$	32.33
Granted	3,431,074	11.35
Vested	(804,962)	31.29
Forfeited	(167,059)	28.77
Nonvested RSUs as of December 31, 2023	5,066,159	$	18.41


	Year ended December 31,
		2023		2022		2021

Weighted average grant date fair value of RSUs granted (per share)		$	11.35	$	30.43	$	143.31
Total fair value of RSUs vested (in thousands)		25,186		15,038		12,571

As of December 31, 2023, total unrecognized compensation cost related to non-vested RSUs was $79.4 million, which will be amortized over a weighted-average period of 2.35 years.

Stock-Based Compensation Expense

The Company recognized total stock-based compensation expense as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
Cost of revenue		$	1,136	$	404	$	364
Research and development		15,661		7,523		3,681
Sales and marketing		6,273		2,808		2,225
General and administrative		13,922		9,920		8,267
Total		$	36,992	$	20,655	$	14,537

Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

The change in the carrying amounts of goodwill was as follows:


	Total

	(In thousands)



Balance as of December 31, 2021	$	344,423

Foreign currency translation adjustments	(18,018)
Balance as of December 31, 2022	326,405
Foreign currency translation adjustments	9,467
Balance as of December 31, 2023	$	335,872

Schedule of Finite Lived Intangible Assets

Intangible assets, net consisted of the following as of December 31, 2023:


	Gross Amount		Accumulated Amortization		Net Carrying Value		Amortization Period

	(In thousands)						(In years)
Customer relationships	$	147,426	$	(35,599)	$	111,827	15 - 20



Developed technology	79,702		(25,239)		54,463		10
Other, definite lived	2,828		(2,828)		—		2 - 7
Licenses, indefinite lived	624		—		624		Indefinite







Total intangible assets, net	$	230,580	$	(63,666)	$	166,914

Intangible assets, net consisted of the following as of December 31, 2022:


	Gross Amount		Accumulated Amortization		Net Carrying Value		Amortization Period

	(In thousands)						(In years)
Customer relationships	$	141,146	$	(25,037)	$	116,109	15 - 20



Developed technology	77,409		(16,772)		60,637		10
Other, definite lived	2,828		(2,828)		—		2 - 7
Licenses, indefinite lived	624		—		624		Indefinite







Total intangible assets, net	$	222,007	$	(44,637)	$	177,370

Schedule of Infinite Lived Intangible Assets

Intangible assets, net consisted of the following as of December 31, 2023:


	Gross Amount		Accumulated Amortization		Net Carrying Value		Amortization Period

	(In thousands)						(In years)
Customer relationships	$	147,426	$	(35,599)	$	111,827	15 - 20



Developed technology	79,702		(25,239)		54,463		10
Other, definite lived	2,828		(2,828)		—		2 - 7
Licenses, indefinite lived	624		—		624		Indefinite







Total intangible assets, net	$	230,580	$	(63,666)	$	166,914

Intangible assets, net consisted of the following as of December 31, 2022:


	Gross Amount		Accumulated Amortization		Net Carrying Value		Amortization Period

	(In thousands)						(In years)
Customer relationships	$	141,146	$	(25,037)	$	116,109	15 - 20



Developed technology	77,409		(16,772)		60,637		10
Other, definite lived	2,828		(2,828)		—		2 - 7
Licenses, indefinite lived	624		—		624		Indefinite







Total intangible assets, net	$	222,007	$	(44,637)	$	177,370

Schedule of Amortization Expense

The Company recognized amortization expense as follows:


	Year ended December 31,
		2023		2022		2021

		(In thousands)
Cost of revenue		$	7,810	$	7,657	$	8,543

Sales and marketing		9,464		9,523		10,576

Total amortization expense		$	17,274	$	17,180	$	19,119

Schedule of Future Estimated Amortization Expense

Future estimated amortization expense for definite lived intangible assets is as follows:


	As of December 31,
	2023

	(In thousands)

2024	$	17,625
2025	17,625
2026	17,625
2027	17,625
2028	17,625

Thereafter	78,165
	$	166,290

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482548/350-20-55-24

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1A

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-2

+ Details