Investments in Unconsolidated Joint Ventures (Schedule of combined financial information for the joint ventures on a 100% basis) (Details) - USD ($) $ in Millions	12 Months Ended
	May 29, 2016	May 31, 2015	May 25, 2014
Schedule of Equity Method Investments [Line Items]
Net sales	$ 2,044.2	$ 2,264.7	$ 2,494.8
Gross margin	867.6	925.4	1,030.3
Earnings before income taxes	234.8	220.9	219.1
Earnings after income taxes	186.7	170.7	168.8
Current assets	814.1	800.1
Noncurrent assets	959.9	962.1
Current liabilities	1,457.3	1,484.8
Noncurrent liabilities	81.7	118.2
Cereal Partners Worldwide [Member]
Schedule of Equity Method Investments [Line Items]
Net sales	1,674.8	1,894.5	2,107.9
Haagen Dazs Japan [Member]
Schedule of Equity Method Investments [Line Items]
Net sales	$ 369.4	$ 370.2	$ 386.9