Equity - Share-based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	$ 119,141	$ 22,958	$ 157,790	$ 57,425
Capitalized stock-based compensation	284	334	1,020	786
Total stock-based compensation	119,425	23,292	158,810	58,211
Cost of revenue
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	13,226	832	15,507	2,682
Sales and marketing
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	39,481	4,802	49,714	15,428
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	39,368	4,411	49,186	10,822
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount
Stock-based compensation, net of amounts capitalized	$ 27,066	$ 12,913	$ 43,383	$ 28,493