Proceeds from termination of interest rate swap contract.

No definition available.

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

- Definition

Reduction of net interest expense due to impact of interest rate swap contracts.

+ References

No definition available.

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Details

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Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 50

-Section 40

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 50

-Section 40

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12355-112629

+ Details

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

- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13, 16

-Article 9

+ Details

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Period Type:	instant

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cag_A2014InterestRateSwapMember
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- Details

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- Details

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- Details

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LONG-TERM DEBT (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended
LONG-TERM DEBT (Narrative) (Details) (USD $)	Nov. 23, 2014	Aug. 24, 2014	Nov. 23, 2014	Nov. 24, 2013	Nov. 24, 2013	Nov. 27, 2010
Debt Instrument [Line Items]
Repayments of Long-term Debt			$ 1,489,400,000us-gaap_RepaymentsOfLongTermDebt	$ 50,700,000us-gaap_RepaymentsOfLongTermDebt
Debt Instrument, Interest Rate, Stated Percentage	3.25%		3.25%
Reduction of net interest expense due to impact of interest rate swap contracts	300,000		600,000
Gains (Losses) on Extinguishment of Debt		(16,300,000)
2010 Interest Rate Swap
Debt Instrument [Line Items]
Reduction of net interest expense due to impact of interest rate swap contracts				4,700,000	2,400,000
Proceeds from termination of interest rate swap contract						28,200,000
2014 Interest Rate Swap
Debt Instrument [Line Items]
Reduction of net interest expense due to impact of interest rate swap contracts	2,600,000		5,200,000
Floating Rate Notes 0.37%
Debt Instrument [Line Items]
Other Notes Payable		550,000,000
Senior Notes \| 2023 Maturity
Debt Instrument [Line Items]
Repayments of Long-term Debt		225,000,000
Senior Notes \| 2043 Maturity
Debt Instrument [Line Items]
Repayments of Long-term Debt	43,000,000	200,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.65%		4.65%
Gains (Losses) on Extinguishment of Debt	2,400,000
Senior Notes \| 2019 Maturity
Debt Instrument [Line Items]
Repayments of Long-term Debt		25,000,000
Senior Notes \| 2018 Maturity
Debt Instrument [Line Items]
Repayments of Long-term Debt		25,000,000
Senior Notes \| 2017 Maturity
Debt Instrument [Line Items]
Repayments of Long-term Debt		25,000,000
LIBOR plus 1.75% term loans
Debt Instrument [Line Items]
Repayments of Long-term Debt		900,000,000
Gains (Losses) on Extinguishment of Debt		(8,300,000)
Tender Premium
Debt Instrument [Line Items]
Gains (Losses) on Extinguishment of Debt		$ 9,500,000
LIBOR \| Floating Rate Notes 0.37%
Debt Instrument [Line Items]
Floating rate notes percentage rate		0.37%
LIBOR \| LIBOR plus 1.75% term loans
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		1.75%