Retirement Plans (Change In Plan Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2020	May 26, 2019	May 27, 2018
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value at beginning of period	$ 248.5
Fair value at end of period		$ 248.5
Defined Benefit Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value at beginning of period	248.5	253.8
Actual return on plan assets	10.5	12.1
Employer contributions	13.2	0.4	$ 60.8
Benefits paid	(272.2)	(17.8)
Fair value at end of period	0.0	248.5	253.8
Postretirement Benefit Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value at beginning of period	0.0	0.0
Actual return on plan assets	0.0	0.0
Employer contributions	1.3	1.3	1.2
Benefits paid	(1.3)	(1.3)
Fair value at end of period	$ 0.0	$ 0.0	$ 0.0