New Accounting Pronouncements (Details) - USD ($) $ in Millions	3 Months Ended
	Aug. 26, 2018	Aug. 27, 2017
Increase (decrease) to benefit plan non-service income, impact of adoption of new accounting standard	$ (20.9)	$ (20.5)
Cumulative effect adjustment related to adoption of new accounting standard	(33.9)
Retained Earnings [Member]
Cumulative effect adjustment related to adoption of new accounting standard	(33.9)
Accounting Standards Update 2017-07 [Member]
Increase (decrease) to benefit plan non-service income, impact of adoption of new accounting standard	(20.9)	(20.5)
Increase (decrease) to operating profit, impact of adoption of new accounting standard	(20.9)	$ (20.5)
Accounting Standards Update 2014-09 [Member] | Deferred Income Tax Charges [Member]
Cumulative effect adjustment related to adoption of new accounting standard	(11.4)
Accounting Standards Update 2014-09 [Member] | Other Current Liabilities [Member]
Cumulative effect adjustment related to adoption of new accounting standard	45.3
Accounting Standards Update 2014-09 [Member] | Retained Earnings [Member]
Cumulative effect adjustment related to adoption of new accounting standard	$ (33.9)