Note 10 - Contingencies (Details Textual) $ in Millions	9 Months Ended	44 Months Ended
Feb. 26, 2023 USD ($)	Feb. 26, 2023 USD ($)
Threshold Amount For Environmental Matters	$ 1.0
Lamb Weston Holdings Inc [Member]
Lessee, Operating Lease, Renewal Term (Year)	5 years	5 years
Beatrice [Member]
Accrual for Environmental Loss Contingencies, Ending Balance	$ 38.7	$ 38.7
Beatrice [Member] \| Other Accrued Liabilities [Member]
Accrual for Environmental Loss Contingencies, Ending Balance	2.0	2.0
Beatrice [Member] \| Other Noncurrent Liabilities [Member]
Accrual for Environmental Loss Contingencies, Ending Balance	36.7	36.7
MPCA [Member]
Accrued Environmental Loss Contingencies, Proposed Penalty Amount	6.8
Performance And Payment Guarantee [Member]
Guarantor Obligations, Maximum Exposure, Undiscounted	75.0	75.0
Property Lease Guarantee [Member]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 9.3	$ 9.3
Lease Remaining Lease Terms (Year)	4 years
CALIFORNIA \| Beatrice [Member]
Litigation Settlement, Amount Awarded to Other Party	$ 101.7
Loss Contingency Settlement Agreement Terms Number Of Installments	7	7
Loss Contingency Accrual, Payments		$ 61.0
CALIFORNIA \| Beatrice [Member] \| Other Accrued Liabilities [Member]
Loss Contingency Accrual, Ending Balance	$ 11.6	11.6
CALIFORNIA \| Beatrice [Member] \| Other Noncurrent Liabilities [Member]
Loss Contingency Accrual, Ending Balance	29.0	$ 29.0
CALIFORNIA \| Beatrice [Member] \| Maximum [Member]
Litigation Settlement Amount Of Guarantee	$ 15.0

The value of proposed penalty amount for environmental loss contingencies.

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- Definition

Represents remaining lease terms.

+ References

No definition available.

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- Definition

Represents amount of guarantee for litigation settlement.

+ References

No definition available.

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Represents number of installments for loss contingency settlement agreement terms.

+ References

No definition available.

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- Definition

Represents threshold amount for environment matters.

+ References

No definition available.

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

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- Definition

Amount of loss contingency liability.

+ References

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- Definition

Amount of cash outflow reducing loss contingency liability.

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