Investments in Joint Ventures (Schedule of combined financial information for the joint ventures on a 100 percent basis) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	May 26, 2013	May 27, 2012	May 29, 2011
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Summarized Financial Information, Revenue	$ 2,552.7	$ 2,581.5	$ 2,452.2
Gross Margin	1,057.3	1,084.1	1,073.6
Earnings before income taxes	260.3	250.3	233.4
Earnings after income taxes	201.6	189.0	164.2
Current assets	976.7	934.8
Noncurrent assets	1,088.2	1,078.0
Current liabilities	1,717.4	1,671.0
Noncurrent liabilities	115.1	91.0
Cereal Partners Worldwide [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Summarized Financial Information, Revenue	2,132.2	2,152.6	2,067.2
Haagen Dazs Japan [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Summarized Financial Information, Revenue	$ 420.5	$ 428.9	$ 385.0