Leases - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Leases [Abstract]
Lease expense	$ 5.1	$ 4.5	$ 3.1
Operating lease not yet commenced amount	$ 1.0
Lessee operating lease not yet commenced, term of contract	4 years 6 months

Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

Name:	us-gaap_LesseeOperatingLeaseLeaseNotYetCommencedTermOfContract1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant