The value of proposed penalty amount for environmental loss contingencies.

No definition available.

Name:	cag_AccruedEnvironmentalLossContingenciesProposedPenaltyAmount
Namespace Prefix:	cag_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents remaining lease terms.

+ References

No definition available.

+ Details

Name:	cag_LeaseRemainingLeaseTerms
Namespace Prefix:	cag_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents amount of guarantee for litigation settlement.

+ References

No definition available.

+ Details

Name:	cag_LitigationSettlementAmountOfGuarantee
Namespace Prefix:	cag_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents number of installments for loss contingency settlement agreement terms.

+ References

No definition available.

+ Details

Name:	cag_LossContingencySettlementAgreementTermsNumberOfInstallments
Namespace Prefix:	cag_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents threshold amount for environment matters.

+ References

No definition available.

+ Details

Name:	cag_ThresholdAmountForEnvironmentalMatters
Namespace Prefix:	cag_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Subparagraph (d)(1)
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Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481931/410-30-50-7

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482425/460-10-50-4

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementAmountAwardedToOtherParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483076/450-20-50-1

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 450
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-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483076/450-20-50-10

+ Details

Name:	us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow reducing loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483076/450-20-50-1

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Note 11 - Contingencies (Details Textual) $ in Thousands		3 Months Ended	12 Months Ended
Note 11 - Contingencies (Details Textual) $ in Thousands	Aug. 23, 2023 USD ($)	Aug. 27, 2023 USD ($)	May 29, 2022 USD ($)	May 30, 2021 USD ($)
Threshold Amount For Environmental Matters			$ 1,000
Accrued Environmental Loss Contingencies, Proposed Penalty Amount	$ 1,250
Lamb Weston Holdings Inc [Member]
Lessee, Operating Lease, Renewal Term (Year)		5 years
Beatrice [Member]
Accrual for Environmental Loss Contingencies		$ 39,800
Beatrice [Member] \| Other Accrued Liabilities [Member]
Accrual for Environmental Loss Contingencies		1,500
Beatrice [Member] \| Other Noncurrent Liabilities [Member]
Accrual for Environmental Loss Contingencies		38,300
Performance And Payment Guarantee [Member]
Guarantor Obligations, Maximum Exposure, Undiscounted		75,000
Property Lease Guarantee [Member]
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 8,000
Lease Remaining Lease Terms (Year)		4 years
CANADA \| Beatrice [Member]
Litigation Settlement, Amount Awarded to Other Party				$ 101,700
Loss Contingency Settlement Agreement Terms Number Of Installments				7
Loss Contingency Accrual, Payments		$ 61,000
CANADA \| Beatrice [Member] \| Other Accrued Liabilities [Member]
Loss Contingency Accrual		11,900
CANADA \| Beatrice [Member] \| Other Noncurrent Liabilities [Member]
Loss Contingency Accrual		28,800
CANADA \| Beatrice [Member] \| Maximum [Member]
Litigation Settlement Amount Of Guarantee		$ 15,000