Stockholders' Equity and Equity Incentive Plans - Summary of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2026	Jan. 31, 2025	Jan. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 760,776	$ 931,309	$ 1,057,161
Benefit from income taxes	(143,661)	(176,463)	(197,068)
Total stock-based compensation expense recorded to net income	617,115	754,846	860,093
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	96,273	124,561	143,798
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	287,172	333,767	336,309
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	254,976	319,631	381,298
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 122,355	$ 153,350	$ 195,756

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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