Cash Equivalents and Short-Term Investments - Schedule of Unrealized Losses Cash Equivalents and Short Term Investment (Details) - USD ($) $ in Thousands	Apr. 30, 2026	Jan. 31, 2026
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	$ 507,705	$ 170,989
Less than 12 months, gross unrealized losses	(997)	(84)
12 months or greater, carrying value	0	0
12 months or greater, gross unrealized losses	0	0
Fair Value	507,705	170,989
Gross Unrealized Losses	(997)	(84)
U.S. Agency securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	63,629	38,754
Less than 12 months, gross unrealized losses	(142)	(28)
12 months or greater, carrying value	0	0
12 months or greater, gross unrealized losses	0	0
Fair Value	63,629	38,754
Gross Unrealized Losses	(142)	(28)
Commercial paper
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	2,412	4,976
Less than 12 months, gross unrealized losses	(1)	0
12 months or greater, carrying value	0	0
12 months or greater, gross unrealized losses	0	0
Fair Value	2,412	4,976
Gross Unrealized Losses	(1)	0
Corporate debt securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	214,667	53,640
Less than 12 months, gross unrealized losses	(398)	(35)
12 months or greater, carrying value	0	0
12 months or greater, gross unrealized losses	0	0
Fair Value	214,667	53,640
Gross Unrealized Losses	(398)	(35)
U.S. Treasury securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	226,997	73,619
Less than 12 months, gross unrealized losses	(456)	(21)
12 months or greater, carrying value	0	0
12 months or greater, gross unrealized losses	0	0
Fair Value	226,997	73,619
Gross Unrealized Losses	$ (456)	$ (21)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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