Equity - Share-based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	$ 301,441	$ 78,399	$ 52,738
Capitalized stock-based compensation	2,072	1,080	577
Total stock-based compensation	303,513	79,479	53,315
Cost of revenue
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	33,642	3,650	1,895
Sales and marketing
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	97,879	20,757	15,647
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	99,223	15,743	28,284
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	$ 70,697	$ 38,249	$ 6,912

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

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