Balance Sheet Components - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Oct. 31, 2020	Jan. 31, 2020
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 102,242	$ 79,527
Less accumulated depreciation and amortization	(57,722)	(44,648)
Property and equipment, net	44,520	34,879
Computer equipment and software
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	71,277	56,758
Furniture, fixtures and equipment
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	1,078	1,028
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	8,271	6,941
Equipment acquired under capital leases
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	17,615	11,687
Construction-in-progress
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 4,001	$ 3,113