Investments in Joint Ventures (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
May 29, 2011	May 30, 2010	May 31, 2009
Investments In Joint Ventures (Details)
Cumulative investments	$ 519.1	$ 398.1
JV Goodwill and other intangibles	597.1	512.6
Aggregate advances	293.3	238.2
Sales to joint ventures	10.2	10.7	14.2
Net advances (repayments)	1.8	128.1	(8.2)
Dividends received	72.7	88.0	68.5
Net sales	2,444.9	2,360.0	2,280.0
Gross Margin	1,066.3	1,053.2	873.5
Earnings before income taxes	233.4	251.2	234.7
Earnings after income taxes	164.2	202.3	175.3
Current assets	904.7	731.7
Noncurrent assets	1,138.0	907.3
Current liabilities	1,690.1	1,322.0
Noncurrent liabilities	$ 103.3	$ 112.1
Additional Information	We have a 50 percent equity interest in Cereal Partners Worldwide (CPW), which manufactures and markets ready-to-eat cereal products in more than 130 countries and republics outside the United States and Canada. CPW also markets cereal bars in several European countries and manufactures private label cereals for customers in the United Kingdom. We have guaranteed a portion of CPW’s debt and its pension obligation in the United Kingdom.
Equity Method Investment Activity At 100 Percent	Summary combined financial information for the joint ventures on a 100 percent basis follows:
Cereal Partners Worldwide [Member]
Investments In Joint Ventures (Details)
Ownership Percentage	50.00%
Haagen Dazs Japan [Member]
Investments In Joint Ventures (Details)
Ownership Percentage	50.00%

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