Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Leases [Abstract]
Operating Lease, Weighted Average Remaining Lease Term	5 years 3 months 18 days
Operating Leases, Rent Expense	$ 86.0	$ 87.2	$ 83.6
Operating Lease, Weighted Average Discount Rate, Percent	4.80%