Balance Sheet Components - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019	Jan. 31, 2020
Property, Plant and Equipment [Line Items]
Sales commissions amortization period	5 years		5 years
Deferred commissions earned and capitalized	$ 15,500	$ 9,100	$ 19,700	$ 15,800
Amortization of deferred commissions	6,300	4,500	12,300	8,700
Depreciation and amortization expense	4,200	3,500	8,200	6,700
Capital lease amortization expense	1,000	$ 1,000	1,900	$ 1,600
Property and equipment, net	38,717		38,717		$ 34,879
Gain on termination of lease					4,000
Gain on reversal of deferred rent					34,500
Impairment of property and equipment					20,700
Cash payments associated with termination and other fees					9,800
Non-US
Property, Plant and Equipment [Line Items]
Property and equipment, net	$ 16,500		$ 16,500		$ 13,400