Note 6 - Investments in Joint Ventures (Details Textual) - USD ($) $ in Millions	12 Months Ended
May 29, 2022	May 30, 2021	May 31, 2020
Related Party Transaction, Purchases from Related Party	$ 30.1	$ 28.7	$ 32.5
Proceeds from Equity Method Investment, Distribution	$ 79.0	$ 56.5	$ 51.4
Ardent Mills [Member]
Equity Method Investment, Ownership Percentage	44.00%	44.00%
Other Joint Ventures [Member]
Equity Method Investment, Ownership Percentage	50.00%	50.00%
Other Assets [Member]
Equity Method Investments	$ 918.3	$ 841.8

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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