Note 12 - Pension and Postretirement Benefits - Schedule of Projected Benefit Obligation, Accumulated Benefit Obligation, and Fair Value of Plan Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Aug. 28, 2022	Aug. 29, 2021
Pension Plan [Member]
Service cost	$ 1.6	$ 2.7
Interest cost	31.0	20.8
Expected return on plan assets	(36.5)	(36.4)
Amortization of prior service cost	0.4	0.5
Total pension and postretirement cost (benefit)	(1.3)	(10.5)
Pension Plan [Member] | Company Plans [Member]
Total pension and postretirement cost (benefit)	(3.5)	(12.4)
Pension Plan [Member] | Multi Employer Plans [Member]
Total pension and postretirement cost (benefit)	2.2	1.9
Other Postretirement Benefits Plan [Member]
Interest cost	0.5	0.3
Amortization of prior service cost	(0.4)	(0.5)
Total pension and postretirement cost (benefit)	(1.0)	(1.0)
Recognized net actuarial gain	$ (1.1)	$ (0.8)