Amounts representing a right to reclaim cash collateral.

No definition available.

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Namespace Prefix:	cag_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Namespace Prefix:	cag_
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- Details

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Namespace Prefix:	cag_
Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Hedge period for the anticipated consumption of commodity inputs.

+ References

No definition available.

+ Details

Name:	cag_HedgePeriodForAnticipatedConsumptionOfCommodityInputs
Namespace Prefix:	cag_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Obligation to return cash collateral.

+ References

No definition available.

+ Details

Name:	cag_ObligationToReturnCashCollateral
Namespace Prefix:	cag_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Proceeds from settlement of interest rate swaps.

+ References

No definition available.

+ Details

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

- Definition

Unrealized loss associated with derivative deferred in accumulated other comprehensive loss.

+ References

No definition available.

+ Details

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Namespace Prefix:	cag_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Monetary amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

+ Details

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Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount recognized in earnings related to the change in fair value during the period of derivative or nonderivative instruments designated as fair value hedging instruments.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount recognized in earnings related to the change in fair value during the period of the hedged item in a fair value hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of the hedged item as of the balance sheet date related to the derivative. For example, the hedged balance on a debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Maximum amount the entity would be obligated to pay on the credit risk derivatives upon occurrence of a credit event.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 15A, 15B, 15C, 15D

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4K

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5708775-113959

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Balance Type:	debit
Period Type:	instant

- Definition

Aggregate notional amount of foreign currency exchange rate derivatives. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

+ Details

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

- Definition

Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5579245-113959

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Derivative Financial Instruments (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
	Feb. 26, 2012	Feb. 26, 2012	Feb. 27, 2011	May 29, 2011
Derivative Financial Instruments (Textual) [Abstract]
Hedge period for the anticipated consumption of commodity inputs		Up to 36 Months
Net notional amount of interest rate derivatives	$ 500.0	$ 500.0
Net gain recognized on interest rate swap contracts			23.0
Net loss recognized on senior long-term debt			29.7
Proceeds from settlement of interest rate swaps	31.5
Unamortized amount of debt instruments being hedged	19.9	19.9
Obligation to return cash collateral	9.1	9.1
Amounts representing a right to reclaim cash collateral included in prepaid expenses and other current assets				7.8
Maximum amount of loss due to the credit risk of the counterparties	62.7	62.7
Forward and cross currency swaps contracts [Member]
Derivatives Fair Value [Abstract]
Net notional value of foreign currency derivatives	390.8	390.8		292.7
Open commodity sales contracts [Member]
Derivatives Fair Value [Abstract]
Notional value of open commodity contracts	916.0	916.0		1,200.0
Open commodity purchase contracts [Member]
Derivatives Fair Value [Abstract]
Notional value of open commodity contracts	1,000.0	1,000.0		1,000.0
Cash Flow Hedging [Member]
Derivatives Fair Value [Abstract]
Unrealized loss associated with derivative deferred in accumulated other comprehensive loss	$ 121.3	$ 121.3