Note 5 - Goodwill and Other Identifiable Intangible Assets (Details Textual) - USD ($) $ in Millions	3 Months Ended
Aug. 28, 2022	Aug. 29, 2021
Fair Value Measurement, Inputs, Terminal Growth Rate	1.00%
Goodwill, Impairment Loss	$ 141.7
Finite-Lived Intangible Assets, Remaining Amortization Period (Year)	18 years
Amortization of Intangible Assets	$ 14.8	$ 14.9
Finite-Lived Intangible Asset, Expected Amortization, Year One	49.3
Finite-Lived Intangible Asset, Expected Amortization, Year Two	49.3
Finite-Lived Intangible Asset, Expected Amortization, Year Three	49.3
Finite-Lived Intangible Asset, Expected Amortization, Year Four	49.3
Finite-Lived Intangible Asset, Expected Amortization, Year Five	49.3
Refrigerated And Frozen [Member]
Goodwill, Impairment Loss	141.7
Selling, General and Administrative Expenses [Member] \| Refrigerated And Frozen [Member]
Goodwill, Impairment Loss	141.7
Selling, General and Administrative Expenses [Member] \| Refrigerated And Frozen [Member] \| Trade Names [Member]
Impairment of Intangible Assets, Indefinite-Lived (Excluding Goodwill)	$ 244.0
Sides Components And Enhancers Reporting Unit [Member]
Fair Value Measurement, Inputs, Discount Rate	7.75%

Percentage used as discount rate to determine fair value measurement.

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Percentage used as growth rate to determine the fair value measurement.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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