Stock-based Compensation (Tables)

9 Months Ended

Oct. 31, 2022

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Classification of Stock-based Compensation

The following table presents the classification of stock-based compensation for the periods indicated:

	Three Months Ended October 31,				Nine Months Ended October 31,
	2022		2021		2022		2021
	(in thousands)
Stock-based compensation:
Cost of revenue	$	360	$	391	$	1,071	$	1,073
Research and development		18,741		13,725		53,775		36,444
Selling, general and administrative		9,000		7,937		27,205		22,750
Total stock-based compensation	$	28,101	$	22,053	$	82,051	$	60,267

Weighted-Average Assumptions Used to Estimate Fair Value

The following table sets forth the weighted-average assumptions used to estimate the fair value of stock options and employee stock purchase plan awards for the periods indicated:

	Three Months Ended October 31,						Nine Months Ended October 31,
	2022			2021			2022			2021
Stock Options:
Volatility		—			—			—			51	%
Risk-free interest rate		—			—			—			0.98	%
Expected term (years)		—			—			—		5.27
Dividend yield		—			—			—			0	%
Employee stock purchase plan awards:
Volatility		72	%		54	%		81	%		57	%
Risk-free interest rate		3.78	%		0.05	%		2.32	%		0.06	%
Expected term (years)	0.5			0.5			0.5			0.5
Dividend yield		0	%		0	%		0	%		0	%

Stock Option Activities

The following table summarizes stock option activities for the period indicated:

	Option Outstanding
										Weighted-
								Total Intrinsic		Average
						Weighted-		Value Of		Remaining		Aggregate
				Weighted-		Average		Options		Contractual		Intrinsic
				Average		Grant-date		Exercised		Term		Value
	Shares			Exercise Price		Fair Value		(in thousands)		(in years)		(in thousands)
Outstanding at January 31, 2022		619,322		$	40.08
Granted		—			—		—
Exercised		(79,880	)		30.79			$	4,696
Forfeited		(7,995	)		49.19
Expired		(1,418	)		19.81
Outstanding at October 31, 2022		530,029			41.40					4.42		$	8,605
Exercisable at October 31, 2022		392,266		$	43.51						3.47	$	5,417

Restricted Stock Unit Activities

The following table summarizes restricted stock unit activities for the period indicated:

				Weighted-
				Average
				Grant-Date
	Shares			Fair Value
Unvested at January 31, 2022		2,651,135		$	85.41
Granted		1,499,374			74.42
Vested		(1,258,895	)		69.81
Forfeited		(77,346	)		101.36
Unvested at October 31, 2022		2,814,268		$	86.40