Stock-based Compensation (Tables)

9 Months Ended

Oct. 31, 2023

Share-Based Payment Arrangement [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,
	2023		2022		2023		2022
	(in thousands)
Stock-based compensation:
Cost of revenue	$	868	$	360	$	2,694	$	1,071
Research and development		17,898		18,741		54,809		53,775
Selling, general and administrative		8,643		9,000		25,293		27,205
Total stock-based compensation	$	27,409	$	28,101	$	82,796	$	82,051

Weighted-Average Assumptions Used to Estimate Fair Value

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

	Three Months Ended October 31,						Nine Months Ended October 31,
	2023			2022			2023			2022
Employee stock purchase plan awards:
Volatility		54	%		72	%		56	%		81	%
Risk-free interest rate		5.49	%		3.78	%		5.11	%		2.32	%
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, 2023		484,791		$	42.18
Exercised		(65,188	)		23.62		$	3,418
Forfeited		(926	)		42.59
Expired		(1,064	)		74.33
Outstanding at October 31, 2023		417,613			45.00					3.68	$	2,584
Exercisable at October 31, 2023		358,750		$	46.30					3.15	$	1,790

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, 2023		2,573,359		$	86.81
Granted		1,190,375			71.77
Vested		(969,060	)		78.11
Forfeited		(128,201	)		76.31
Unvested at October 31, 2023		2,666,473		$	83.76