Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Schedule of Stock-based Compensation Expense

Stock-based compensation expense included in the consolidated statements of operations was as follows:

	Year Ended December 31,
(in thousands)	2023		2022		2021
Cost of revenue	$	11,247	$	8,369	$	4,446
Sales and marketing	61,322		49,383		29,410
Research and development	37,225		31,499		20,593
General and administrative	35,533		31,382		24,956
Total stock-based compensation expense	$	145,327	$	120,633	$	79,405

Schedule of RSUs and PSUs

A summary of our restricted stock, RSU and PSU activity is presented below:

	Restricted Stock			RSUs			PSUs
(in thousands, except for per share data)	Number of Shares	Weighted Average Grant Date Fair Value		Number of Shares	Weighted Average Grant Date Fair Value		Number of Shares	Weighted Average Grant Date Fair Value
Unvested balance at December 31, 2020	99	$	4.25	4,490	$	28.13	—	$	—
Granted	—	—		3,842	43.57		—	—
Vested	(99)	4.25		(1,872)	28.14		—	—
Forfeited	—	—		(679)	33.64		—	—
Unvested balance at December 31, 2021	—	—		5,781	37.74		—	—
Granted	—	—		4,653	45.83		209	44.97
Vested	—	—		(2,510)	36.47		—	—
Forfeited	—	—		(1,030)	40.45		(13)	44.97
Unvested balance at December 31, 2022	—	—		6,894	43.26		196	44.97
Granted	311	45.67		4,728	43.47		188	43.24
Performance adjustment(1)	—	—		—	—		12	44.97
Vested	—	—		(3,153)	41.61		(91)	44.97
Forfeited	—	—		(1,126)	45.14		(47)	43.92
Unvested balance at December 31, 2023	311	45.67		7,343	43.80		258	43.90

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(1)    Represents adjustments due to the achievement of predefined financial performance targets.

Schedule of Stock Option Activity

A summary of our stock option activity is presented below:

(in thousands, except for per share data and years)	Number of Shares	Weighted Average Exercise Price		Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
Outstanding at December 31, 2020	9,441	$	8.56	6.4	$	412,547
Exercised	(2,671)	6.84			111,256
Forfeited/canceled	(39)	14.96
Outstanding at December 31, 2021	6,731	9.21		5.5	308,677
Exercised	(1,174)	9.98			47,880
Forfeited/canceled	(72)	16.15
Outstanding at December 31, 2022	5,485	8.96		4.5	160,135
Exercised	(387)	9.05			13,364
Forfeited/canceled	(3)	10.97
Outstanding and exercisable at December 31, 2023	5,095	8.95		3.5	189,108

Schedule of ESPP Valuation Assumptions

The fair value of the 2018 ESPP purchase rights was estimated on the offering or modification dates using a Black-Scholes option-pricing model and the following assumptions:

	Year Ended December 31,
	2023	2022	2021
Expected term (in years)	0.5 — 2.0	0.5 — 2.0	0.5 — 2.0
Expected volatility	46.9% — 58.1%	42.8% — 61.0%	37.2% — 59.4%
Risk-free interest rate	4.8% — 5.4%	0.1% — 3.4%	0.1% — 0.2%
Expected dividend yield	—	—	—