Note 13 - Pension and Postretirement Benefits (Details Textual) - USD ($) $ in Millions		2 Months Ended	3 Months Ended		9 Months Ended
	May 29, 2023	Feb. 25, 2024	Feb. 25, 2024	Feb. 26, 2023	Feb. 25, 2024	Feb. 26, 2023	Dec. 31, 2023	May 28, 2023
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), before Tax			$ (6.8)
Pension Plan [Member]
Defined Benefit Plan, Plan Assets, Payment for Settlement			135.0
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate							5.20%	5.52%
Defined Benefit Plan, Service Cost Assumptions Used Calculating Net Periodic Benefit Cost Discount Rate	5.64%	5.60%
Defined Benefit Plan, Interest Cost Assumptions Used Calculating Net Periodic Benefit Cost Discount Rate	5.44%	5.41%
Defined Benefit Plan, Plan Assets, Contributions by Employer			3.2	$ 1.7		$ 4.7
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		$ 2.9	2.9		$ 2.9
Postemployment Retirement Benefits [Member]
Defined Benefit Plan, Plan Assets, Contributions by Employer					9.2
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		$ 2.5	$ 2.5		$ 2.5