Leases - Lease Cost in Statements of Earnings (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Lessee, Lease, Description [Line Items]
Fixed operating lease expense		$ 76.4	$ 79.2	$ 225.0	$ 234.2
Variable operating lease expense	[1]	40.6	40.3	77.9	110.7
Sublease income		(1.3)	(1.7)	(3.8)	(4.1)
Net lease expense		115.7	$ 117.8	299.1	$ 340.8
Asia-Pacific | COVID-19
Lessee, Lease, Description [Line Items]
Rent concessions		$ 10.0		$ 31.4

[1] Includes a credit of $10.0 million and $31.4 million in the three and nine months ended October 31, 2020, respectively, related to rent concessions negotiated in connection with retail store closures due to COVID-19.