Note 15 - Business Segments and Related Information - Presentation of Derivative Gains (Losses) from Economic Hedges of Forecasted Cash Flows in Segment Results (Details) - Cash Flow Hedging [Member] - Designated as Hedging Instrument [Member] - USD ($) $ in Millions	3 Months Ended
	Aug. 28, 2022	Aug. 29, 2021
Net derivative gains (losses)	$ 9.5	$ 10.2
Operating Segments [Member]
Net derivative gains (losses)	9.0	5.0
Operating Segments [Member] | Grocery And Snacks [Member]
Net derivative gains (losses)	5.0	3.2
Operating Segments [Member] | Refrigerated And Frozen [Member]
Net derivative gains (losses)	3.3	4.7
Operating Segments [Member] | International [Member]
Net derivative gains (losses)	0.1	(3.2)
Operating Segments [Member] | Foodservice [Member]
Net derivative gains (losses)	0.6	0.3
Segment Reconciling Items [Member]
Net derivative gains (losses)	$ 0.5	$ 5.2