Cash Equivalents and Short-Term Investments - Schedule of Unrealized Losses Cash Equivalents and Short Term Investment (Details) - USD ($) $ in Thousands	Jul. 31, 2025	Jan. 31, 2025
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	$ 740,363	$ 234,818
Less than 12 months, gross unrealized losses	(821)	(362)
12 months or greater, carrying value	0	5,988
12 months or greater, gross unrealized losses	0	(2)
Fair Value	740,363	240,806
Gross Unrealized Losses	(821)	(364)
U.S. Agency securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	63,894	48,445
Less than 12 months, gross unrealized losses	(81)	(65)
12 months or greater, carrying value	0	0
12 months or greater, gross unrealized losses	0	0
Fair Value	63,894	48,445
Gross Unrealized Losses	(81)	(65)
Commercial paper
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	25,706	13,430
Less than 12 months, gross unrealized losses	(11)	(11)
12 months or greater, carrying value	0	0
12 months or greater, gross unrealized losses	0	0
Fair Value	25,706	13,430
Gross Unrealized Losses	(11)	(11)
Corporate debt securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	155,060	72,022
Less than 12 months, gross unrealized losses	(224)	(146)
12 months or greater, carrying value	0	5,988
12 months or greater, gross unrealized losses	0	(2)
Fair Value	155,060	78,010
Gross Unrealized Losses	(224)	(148)
U.S. Treasury securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 months, carrying value	495,703	100,921
Less than 12 months, gross unrealized losses	(505)	(140)
12 months or greater, carrying value	0	0
12 months or greater, gross unrealized losses	0	0
Fair Value	495,703	100,921
Gross Unrealized Losses	$ (505)	$ (140)

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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