Note 11 - Pension and Postretirement Benefits (Details Textual) $ in Millions	3 Months Ended	9 Months Ended
	Feb. 26, 2023 USD ($)	Feb. 26, 2023 USD ($)
Pension Plan [Member]
Defined Benefit Plan, Service Cost Assumptions Used Calculating Net Periodic Benefit Cost Discount Rate		4.74%
Defined Benefit Plan, Interest Cost Assumptions Used Calculating Net Periodic Benefit Cost Discount Rate		4.09%
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 3.7	$ 9.6
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year	2.8	2.8
Postemployment Retirement Benefits [Member]
Defined Benefit Plan, Plan Assets, Contributions by Employer	1.5	5.1
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year	$ 3.0	$ 3.0