Marketable Securities - Schedule of Marketable Securities (Details) - USD ($) $ in Thousands	Jan. 31, 2024	Jan. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 818,246	$ 358,335
Gross Unrealized Gains	29	0
Gross Unrealized Losses	(130)	(619)
Estimated Fair Value	818,145	357,716
Cash and cash equivalents, amortized cost	1,061,678	1,402,119
Treasury bills & U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	641,263	234,848
Gross Unrealized Gains	29	0
Gross Unrealized Losses	(100)	(308)
Estimated Fair Value	641,192	234,540
Treasury bills
Debt Securities, Available-for-sale [Line Items]
Cash and cash equivalents, amortized cost		10,000
Cash and cash equivalents, fair value		10,000
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		62,470
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		62,470
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,993	46,684
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2)	(198)
Estimated Fair Value	1,991	46,486
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		6,374
Gross Unrealized Gains		0
Gross Unrealized Losses		(66)
Estimated Fair Value		6,308
Agency bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	174,990	7,959
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(28)	(47)
Estimated Fair Value	$ 174,962	$ 7,912