Note 12 - Contingencies (Details Textual) $ in Millions		6 Months Ended
	Oct. 31, 2023 USD ($)	Nov. 26, 2023 USD ($)	May 28, 2023 USD ($)
Threshold Amount For Environmental Matters		$ 1.0
Lamb Weston Holdings Inc [Member]
Lessee, Operating Lease, Renewal Term (Year)		5 years
Threatened Litigation [Member]
Loss Contingency Accrual		$ 54.5	$ 51.3
Reese v. Conagra Brands, Inc. [Member] | Damages from Product Defects [Member] | Judicial Ruling For Compensatory Damages [Member]
Loss Contingency, Damages Awarded, Value	$ 3.1
Reese v. Conagra Brands, Inc. [Member] | Damages from Product Defects [Member] | Judicial Ruling For Punitive Damages [Member]
Loss Contingency, Damages Awarded, Value	$ 4.0
Other Accrued Liabilities [Member] | Threatened Litigation [Member]
Loss Contingency Accrual		26.1	22.4
Other Noncurrent Liabilities [Member] | Threatened Litigation [Member]
Loss Contingency Accrual		28.4	28.9
Beatrice [Member]
Accrual for Environmental Loss Contingencies		38.8	40.1
Beatrice [Member] | Other Accrued Liabilities [Member]
Accrual for Environmental Loss Contingencies		1.5	1.5
Beatrice [Member] | Other Noncurrent Liabilities [Member]
Accrual for Environmental Loss Contingencies		37.3	38.6
Performance And Payment Guarantee [Member]
Guarantor Obligations, Maximum Exposure, Undiscounted		75.0
Property Lease Guarantee [Member]
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 7.4
Lease Remaining Lease Terms (Year)		3 years
CALIFORNIA | Beatrice [Member]
Litigation Settlement, Amount Awarded to Other Party		$ 101.7
Loss Contingency Settlement Agreement Terms Number Of Installments		7
Loss Contingency Accrual, Payments		$ 73.0
Loss Contingency Accrual		28.8	40.7
CALIFORNIA | Beatrice [Member] | Other Accrued Liabilities [Member]
Loss Contingency Accrual		11.6	11.8
CALIFORNIA | Beatrice [Member] | Other Noncurrent Liabilities [Member]
Loss Contingency Accrual		17.2	$ 28.9
CALIFORNIA | Beatrice [Member] | Maximum [Member]
Litigation Settlement Amount Of Guarantee		$ 15.0