Stockholders' Equity and Equity Incentive Plans - Summary of Stock-based Compensation Expense by Line Item (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 477,287	$ 275,818	$ 73,109
Benefit from income taxes	(84,245)	0	0
Total stock-based compensation expense recorded to net income	393,042	275,818	73,109
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	69,612	34,960	7,860
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	113,000	50,161	11,645
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	229,297	146,377	41,465
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 65,378	$ 44,320	$ 12,139

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

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