GOODWILL AND OTHER IDENTIFIABLE INTANGIBLE ASSETS (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 23, 2014	Nov. 23, 2014	May 25, 2014
Goodwill [Line Items]
Weighted average life in years of amortizing intangible assets		21 years
Amortization expense year one	$ 108.3	$ 108.3
Amortization expense year two	108.3	108.3
Amortization expense year three	108.3	108.3
Amortization expense year four	108.3	108.3
Amortization expense year five	108.3	108.3
Impairment	216.6us-gaap_GoodwillImpairmentLoss	216.6us-gaap_GoodwillImpairmentLoss
Goodwill	7,616.8us-gaap_Goodwill	7,616.8us-gaap_Goodwill	7,828.5us-gaap_Goodwill
Bars and Coordinated
Goodwill [Line Items]
Impairment	31.9
Goodwill	296.8	296.8
Cereal
Goodwill [Line Items]
Impairment	18.1
Goodwill	446.3	446.3
Snacks
Goodwill [Line Items]
Impairment	146.6
Goodwill	668.7	668.7
Retail Bakery
Goodwill [Line Items]
Impairment	20.0
Goodwill	695.2	695.2
Pasta
Goodwill [Line Items]
Goodwill	748.8	748.8
Condiments
Goodwill [Line Items]
Goodwill	136.1	136.1
Private Brands
Goodwill [Line Items]
Discount Rate	8.00%
Terminal Growth Rate	3.00%
Number of reporting units with fair value less than carrying value	5
Impairment	216.6	216.6
Number of reporting units with fair value substantially less than carrying value	2
Goodwill	2,991.9	2,991.9	3,214.6
Impairment charges	$ 30.0
Number of brands impaired	3

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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