Deferred Revenue, Performance Obligations, and Unbilled Accounts Receivable - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019	Jan. 31, 2020
Revenue From Contracts With Customers [Line Items]
Unbilled accounts receivable	$ 53,235		$ 53,235		$ 32,817
Subscription services
Revenue From Contracts With Customers [Line Items]
Recognition of deferred revenue	232,000	$ 178,000	409,000	$ 311,000
Revenue expected to be recognized from remaining performance obligations	772,000		772,000
Unbilled accounts receivable	30,000		30,000		15,000
Professional services and other
Revenue From Contracts With Customers [Line Items]
Unbilled accounts receivable	$ 23,000		$ 23,000		$ 18,000