Retirement Plans (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Nov. 24, 2019	Nov. 24, 2019	Nov. 25, 2018	Nov. 24, 2019	Nov. 25, 2018
Defined Benefit Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost		$ 1.6	$ 2.2	$ 3.2	$ 4.6
Expected return on plan assets		(2.0)	(2.8)	(4.0)	(5.6)
Pension settlement expense	$ 147.1	147.1	0.0	147.1	0.0
Recognized net actuarial loss		0.8	0.7	1.7	1.3
Net periodic benefit cost		147.5	0.1	148.0	0.3
Employer contributions		12.2
Postretirement Benefit Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost		0.1	0.2	0.3	0.4
Unrecognized prior service cost		(1.1)	(1.2)	(2.3)	(2.4)
Recognized net actuarial loss		0.3	0.4	0.7	0.8
Net periodic benefit cost		$ (0.7)	$ (0.6)	$ (1.3)	$ (1.2)