Leases (Details) $ in Millions	3 Months Ended
	Apr. 30, 2019 USD ($) Rate
Leases [Abstract]
Operating Lease, Weighted Average Remaining Lease Term	4 years 10 months 24 days
Operating Lease, Weighted Average Discount Rate, Percent | Rate	4.80%
Operating Leases, Rent Expense | $	$ 21.6