Leases - Additional Information (Details)	6 Months Ended
Jul. 31, 2019
Minimum
Lessee Lease Description [Line Items]
Operating leases, remaining terms	1 year
Operating leases, option to extend	true
Maximum
Lessee Lease Description [Line Items]
Operating leases, remaining terms	11 years

Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

Name:	us-gaap_LesseeOperatingLeaseOptionToExtend
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration