Financial Instruments and Fair Value - Schedule of Available-for-Sale Securities at Fair Value (Detail) - USD ($) $ in Thousands	Oct. 31, 2021	Jan. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 20	$ 213,583
Unrealized Gains	0	1,226
Unrealized Losses	0	(7)
Fair Value	20	214,802
Money market funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20	171
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	20	171
Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	0	66,181
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	0	66,181
Corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	0	102,108
Unrealized Gains	0	980
Unrealized Losses	0	(7)
Fair Value	0	103,081
Asset-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	0	15,740
Unrealized Gains	0	164
Unrealized Losses	0	0
Fair Value	0	15,904
U.S. government securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	0	29,383
Unrealized Gains	0	82
Unrealized Losses	0	0
Fair Value	$ 0	$ 29,465

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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