Basis of Presentation and Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue	$ 592,049	$ 264,748	$ 96,666
Product revenue
Disaggregation of Revenue [Line Items]
Revenue	553,794	252,229	95,683
Professional services and other revenue
Disaggregation of Revenue [Line Items]
Revenue	$ 38,255	$ 12,519	$ 983