Stockholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	May 31, 2020	May 26, 2019	May 27, 2018
Cummulative preference stock, shared authorized	5.0
Number of shares of common stock authorized for repurchase	100.0
Shares issued, shares			22.7
Common stock, par value	$ 0.10	$ 0.1	$ 0.10
Shares issued, price per share			$ 44.00
Total proceeds from issuance of stock			$ 1,000.0
Proceeds from common stock issued	$ 0.0	$ 0.0	969.9
Payment of stock issuance costs			$ 30.1
Shares purchased	0.1	0.0	10.9
Aggregate purchase price	$ 3.4	$ 1.1	$ 601.6
Retained Earnings [Member]
Reclassification from AOCI to retained earnings, stranded income tax effects resulting from the Tax Cuts and Jobs Act of 2017	0.0	0.0	329.4
AOCI [Member]
Reclassification from AOCI to retained earnings, stranded income tax effects resulting from the Tax Cuts and Jobs Act of 2017	$ 0.0	$ 0.0	$ (329.4)