Cumulative Derivative Gains (Losses) Recognized, Not Yet Reclassified To Segment Operating Results

No definition available.

Name:	cag_CumulativeDerivativeGainsLossesRecognizedNotYetReclassifiedToSegmentOperatingResults
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- Definition

Derivative gains (losses) of previous year to be reclassified to segment operating results.

+ References

No definition available.

+ Details

Name:	cag_DerivativeGainLossOfPreviousYearToBeReclassifiedToSegmentOperatingResults
Namespace Prefix:	cag_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Derivative gain (loss) to be reclassified to segment operating results thereafter.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Derivative Gains (Losses) To Be Reclassified To Segment Operating Results Next Fiscal Year

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_EntityWideRevenueMajorCustomerLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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Namespace Prefix:
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Balance Type:
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- Details

Name:	us-gaap_MajorCustomersAxis=cag_WalMartStoresInc.AndAffiliatesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AccountsReceivableMember
Namespace Prefix:
Data Type:	na
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Period Type:

BUSINESS SEGMENTS AND RELATED INFORMATION - Narrative (Details) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Nov. 27, 2016 USD ($)	Nov. 29, 2015	Nov. 27, 2016 USD ($) segment	Nov. 29, 2015	May 29, 2016 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment			5
Cumulative net derivative gains from economic hedges recognized in general and corporate expenses	$ 2.0		$ 2.0
Net gains incurred during current fiscal year			1.9
Derivative gains incurred prior to fiscal 2017					$ 0.1
Gains expected to be reclassified in fiscal 2017			1.6
Gains expected to be reclassified in fiscal 2018 and thereafter			$ 0.4
Customer concentration risk \| Net sales \| Wal-Mart Stores, Inc. and affiliates
Revenue, Major Customer [Line Items]
Concentration risk (as a percent)	24.00%	23.00%	23.00%	23.00%
Customer concentration risk \| Net receivables \| Wal-Mart Stores, Inc. and affiliates
Revenue, Major Customer [Line Items]
Concentration risk (as a percent)			24.00%		24.00%