Significant Accounting Policies - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018	Feb. 01, 2019	Jan. 31, 2019
Significant Accounting Policies [Line Items]
Subscriptions revenue contracts term			3 years
Accounts receivable, net of allowances	$ 79,658,000		$ 79,658,000			$ 95,274,000
Unbilled receivables	5,300,000		5,300,000			$ 1,500,000
Revenue expected to be recognized from remaining performance obligation	593,300,000		593,300,000
Revenue recognized from performance obligations satisfied in prior periods	881,000		326,000
Revenue recognized from deferred revenue	$ 81,500,000		$ 160,600,000
Deferred commission, amortization period	5 years		5 years
Capitalized commission costs	$ 5,600,000	$ 3,200,000	$ 15,500,000	$ 17,500,000
Amortization of deferred commissions	2,400,000	$ 1,500,000	6,700,000	$ 4,200,000
Operating lease right-of-use assets	31,657,000		31,657,000		$ 27,300,000
Operating lease liabilities	33,419,000		$ 33,419,000		28,900,000
Deferred rent					$ 1,600,000
Maximum
Significant Accounting Policies [Line Items]
Payment terms of customers			30 days
Other Assets
Significant Accounting Policies [Line Items]
Long-term unbilled receivables	$ 881,000		$ 881,000