Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2022

Share-Based Payment Arrangement [Abstract]

Stock-based compensation expense

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

	Three Months Ended September 30,				Nine Months Ended September 30,
(in thousands)	2022		2021		2022		2021
Cost of revenue	$	2,341	$	1,197	$	5,968	$	3,336
Sales and marketing	13,589		7,629		36,420		21,502
Research and development	8,754		5,587		23,294		14,919
General and administrative	7,959		6,499		24,272		18,576
Total stock-based compensation expense	$	32,643	$	20,912	$	89,954	$	58,333

Summary of RSUs and PSUs

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

	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
Unvested balance at December 31, 2021	5,781	$	37.74	—	$	—
Granted	4,377	46.21		209	44.97
Vested	(1,939)	36.04		—	—
Forfeited	(704)	39.05		—	—
Unvested balance at September 30, 2022	7,515	42.98		209	44.97

Stock option activity

A summary of our stock option activity is presented below:

(in thousands, except for exercise prices and years)	Number of Shares	Weighted Average Exercise Price		Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
Outstanding at December 31, 2021	6,731	$	9.21	5.5	$	308,677
Granted	—	—
Exercised	(1,090)	9.78			45,668
Forfeited/canceled	(72)	16.15
Outstanding and exercisable at September 30, 2022	5,569	9.01		4.7	143,630

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:

	Nine Months Ended September 30,
	2022	2021
Expected term (in years)	0.5 — 2.0	0.5 — 2.0
Expected volatility	42.8% — 61.0%	37.2% — 59.4%
Risk-free interest rate	0.1% — 3.4%	0.1% — 0.2%
Expected dividend yield	—	—