LEASES - Lease Expense - Total (Details) $ in Millions	12 Months Ended
	May 31, 2020 USD ($)
Lease expense
Operating lease costs	$ 29.7
Short-term and variable lease costs	5.8
Sublease income	(2.7)
Amortization of lease assets	3.2
Interest on lease liabilities	0.6
Total lease costs, net	$ 36.6