Name:	gis_NoncontrollingInterestFairValueAmount
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Period Type:	instant

Maximum number of years in which redeemable interest holder has the ability to put a limited portion of its redeemable interest to the company at fair value once per year.

No definition available.

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Data Type:	xbrli:durationItemType
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The percentage points added to the floating preferred return rate to compute the variable rate on preferred distributions.

No definition available.

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Data Type:	num:percentItemType
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Period Type:	duration

The reference rate for the variable rate of the preferred distributions, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

No definition available.

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The time period between scheduled adjustments of the preferred return rate.

No definition available.

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The percent ownership as of the reporting date of noncontrolling interests which the parent entity is required to redeem (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity.

No definition available.

Name:	gis_RedeemableInterestPercentOwnership
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Data Type:	num:percentItemType
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Period Type:	duration

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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 210.5-02.31)

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 27

-Article 5

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 20

-Article 7

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The fair value as of the reporting date of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) is represented by an equity interest that does not conform to either common or preferred equity (noncontrolling) interests otherwise provided for in the taxonomy, regardless of investee entity legal form.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph (16)(c)

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph (12)(c)

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph 15

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph 14

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

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- Details

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Amount of transactions with related party during the financial reporting period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864