Goodwill and Other Identifiable Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Feb. 26, 2012	May 29, 2011
Change in the carrying amount of goodwill
Goodwill, Beginning Balance	$ 3,609.4
Acquisitions	310.0
Foreign currency translation	7.9
Goodwill, Ending Balance	3,927.3
Other identifiable intangible assets
Non-amortizing intangible assets, gross carrying amount	872.5	771.2
Non-amortizing intangible assets, accumulated amortization
Amortizing intangible assets, gross carrying amount	286.0	213.9
Amortizing intangible assets, accumulated amortization	63.8	48.8
Intangible assets, gross carrying amount	1,158.5	985.1
Consumer foods [Member]
Change in the carrying amount of goodwill
Goodwill, Beginning Balance	3,479.7
Acquisitions	310.0
Foreign currency translation	8.4
Goodwill, Ending Balance	3,798.1
Commercial foods [Member]
Change in the carrying amount of goodwill
Goodwill, Beginning Balance	129.7
Foreign currency translation	(0.5)
Goodwill, Ending Balance	$ 129.2

Indefinite lived intangible assets accumulated amortization.

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Intangible assets gross excluding goodwill.

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The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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The aggregate amount of goodwill acquired in the period and allocated to the reportable segment. The value is stated at fair value based on the purchase price allocation.

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The increase (decrease) in the recorded value of goodwill for foreign currency translation adjustments and purchase accounting adjustments needed to revise the carrying amount of goodwill to fair value.

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Carrying amount of intangible assets, excluding goodwill, which have a projected indefinite period of benefit (hence are not amortized), allocated to the reportable segment. These assets, acquired either individually or as part of a group of assets, in either an asset acquisition or business combination, are assessed at least annually for impairment. Examples may include trade secrets, contractual rights, trade names, and licensing agreements.

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