Investments in Unconsolidated Joint Ventures (Narrative) (Details)	12 Months Ended
May 27, 2018 country
Cereal Partners Worldwide [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Annual reporting period ended March 31	12 months
Cereal Partners Worldwide [Member] \| Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Number of countries in which entity operates	130
Haagen Dazs Japan [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Annual reporting period ended March 31	12 months

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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Duration of a fiscal period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter.

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The number of countries in which the entity operates as of balance sheet date.

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