Restructuring, Impairment, and Other Exit Costs (Schedule of restructuring and other exit cost reserves) (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2020	May 26, 2019	May 27, 2018
Restructuring Reserve [Roll Forward]
Reserve beginning balance	$ 36.5	$ 66.8	$ 85.0
Restructuring charges paid out of reserve, including foreign currency translation	(2.5)	11.6	40.3
Restructuring reserve utilized	(16.2)	(41.9)	(58.5)
Reserve ending balance	17.8	36.5	66.8
Severance [Member]
Restructuring Reserve [Roll Forward]
Reserve beginning balance	36.5	66.0	81.8
Restructuring charges paid out of reserve, including foreign currency translation	(5.0)	7.7	40.8
Restructuring reserve utilized	(13.7)	(37.2)	(56.6)
Reserve ending balance	17.8	36.5	66.0
Contract Termination [Member]
Restructuring Reserve [Roll Forward]
Reserve beginning balance	0.0	0.1	0.7
Restructuring charges paid out of reserve, including foreign currency translation	0.8	2.5	0.2
Restructuring reserve utilized	(0.8)	(2.6)	(0.8)
Reserve ending balance	0.0	0.0	0.1
Other Exit Costs [Member]
Restructuring Reserve [Roll Forward]
Reserve beginning balance	0.0	0.7	2.5
Restructuring charges paid out of reserve, including foreign currency translation	1.7	1.4	(0.7)
Restructuring reserve utilized	(1.7)	(2.1)	(1.1)
Reserve ending balance	$ 0.0	$ 0.0	$ 0.7