Marketable Securities - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Apr. 30, 2024	Jan. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 790,488	$ 818,246
Gross Unrealized Gains	0	29
Gross Unrealized Losses	(606)	(130)
Estimated Fair Value	789,882	818,145
Cash and cash equivalents, amortized cost	1,146,618	1,061,678
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	978
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Estimated Fair Value	978
Treasury bills and U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	710,071	641,263
Gross Unrealized Gains	0	29
Gross Unrealized Losses	(506)	(100)
Estimated Fair Value	709,565	641,192
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	24,778	1,993
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(60)	(2)
Estimated Fair Value	24,718	1,991
Cash and cash equivalents, amortized cost	6,100
Cash and cash equivalents, fair value	6,100
Agency bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	54,661	174,990
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(40)	(28)
Estimated Fair Value	54,621	$ 174,962
Treasury bills
Debt Securities, Available-for-sale [Line Items]
Cash and cash equivalents, amortized cost	19,800
Cash and cash equivalents, fair value	$ 19,800