Leases - Additional Information (Detail) $ in Millions	3 Months Ended
	Apr. 30, 2019 USD ($)
Leases [Abstract]
Lease, year of expiration	The leases expire at various dates through fiscal year 2028
Operating leases, existence of options to extend	true
Operating leases, options to extend description	some of which include options to extend the lease for up to 3 years.
Operating leases, extended term	3 years
Operating lease expense	$ 0.7