Additional Financial Information (Supplemental Cash Flow Information) (Details) - USD ($) $ in Millions	9 Months Ended
	Feb. 28, 2021	Feb. 23, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interest, net of amounts capitalized	$ 45.7	$ 40.2
Income taxes, net of refunds	12.4	1.1
Increase in land, buildings and equipment through accrued purchases	29.8	44.7
Right-of-use assets obtained in exchange for new operating lease liabilities	30.1	164.5
Right-of-use assets obtained in exchange for new finance lease liabilities	$ 128.1	$ 166.2