Stock-Based Compensation - Awards Available for Grant (Details) - shares	9 Months Ended	12 Months Ended
	Oct. 31, 2021	Jan. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Awards Available For Grant [Roll Forward]
Balance, beginning of period (in shares)	4,796,000
Awards authorized (in shares)	22,532,000	5,788,000
Options granted (in shares)	(7,919,000)	(4,622,000)
Options cancelled and forfeited (in shares)	1,701,000	1,970,000
Options repurchased (in shares)	90,000	120,000
Balance, end of period (in shares)	18,200,000	1,540,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Awards Available For Grant [Roll Forward]
Grants in period (in shares)	(3,000,000)	0