Leases (Narrative) (Details) $ in Millions	6 Months Ended
	Jul. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease not yet commenced undiscounted amount	$ 17.1
Operating lease not yet commenced term of contract	11 years
Minimum
Lessee, Lease, Description [Line Items]
Remaining operating lease terms	3 years
Lease renewal terms extension	3 years
Maximum
Lessee, Lease, Description [Line Items]
Remaining operating lease terms	11 years
Lease renewal terms extension	10 years