Supplemental Information (Details) (USD $) In Millions	12 Months Ended
	May 29, 2011	May 30, 2010	May 31, 2009
Receivables [Abstract]
From customers	$ 1,178.6	$ 1,057.4
Less allowance for doubtful accounts	(16.3)	(15.8)
Total	1,162.3	1,041.6
Inventory [Abstract]
Raw materials and packaging	286.2	247.5
Finished goods	1,273.6	1,131.4
Grain	218.0	107.4
Excess of FIFO or weighted-average cost over LIFO cost	(168.5)	(142.3)
Total	1,609.3	1,344.0
LIFO Inventory Amount	1,034.1	958.3
Prepaid Expenses And Other Assets Current [Abstract]
Prepaid expenses	161.0	127.5
Accrued interest receivable, including interest rate swaps	29.0	64.9
Derivative receivables, primarily commodity-related	109.1	48.8
Other receivables	104.7	101.4
Grain Derivative Asset Not Designated As Hedging Instrument Fair Value Current	57.3	11.4
Miscellaneous	22.4	24.5
Total	483.5	378.5
Land Buildings And Equipment [Abstract]
Land	61.2	58.0
Buildings	1,777.7	1,653.8
Buildings under capital lease	25.0	19.6
Equipment	4,719.7	4,405.6
Equipment under capital lease	18.9	25.0
Capitalized Software	367.7	318.7
Construction in progress	521.9	469.0
Total land, buildings, and equipment	7,492.1	6,949.7
Less accumulated depreciation	(4,146.2)	(3,822.0)
Total	3,345.9	3,127.7
Other Noncurrent Assets [Abstract]
Pension assets	128.6	2.2
Investments in and advances to joint ventures	519.1	398.1
Life insurance	87.2	88.2
Non-current derivative receivables	13.3	130.1
Miscellaneous	114.3	144.8
Total	862.5	763.4
Other Current Liabilities [Abstract]
Accrued payroll	303.3	331.4
Accrued interest	114.0	136.5
Accrued trade and consumer promotions	463.0	555.2
Accrued taxes	80.4	440.2
Derivatives payable	34.8	18.1
Accrued customer advances	36.4	25.5
Grain Derivative Liability Not Designated As Hedging Instrument Fair Value Current	28.7	12.7
Miscellaneous	260.9	242.6
Total	1,321.5	1,762.2
Other Noncurrent Liabilities [Abstract]
Interest rate swaps	22.2	180.2
Accrued compensation and benefits, including obligations for underfunded other postretirement and postemployment benefit plans	1,412.8	1,588.1
Accrued income taxes	233.3	276.3
Miscellaneous	64.9	74.1
Total	1,733.2	2,118.7
Earnings Supplemental [Abstract]
Depreciation and amortization	472.6	457.1	453.6
Research and development expense	235.0	218.3	208.2
Advertising and media expense (including production and communication costs)	843.7	908.5	732.1
Interest Net [Abstract]
Interest expense	360.9	374.5	409.5
Capitalized interest	(7.2)	(6.2)	(5.1)
Interest income	(7.4)	(6.8)	(21.6)
Loss on debt repurchase	0	40.1	0
Total	346.3	401.6	382.8
Cash Flows [Abstract]
Cash interest payments	333.1	384.1	292.8
Cash paid for income taxes	699.3	672.5	395.3
Shares issued for acquisition, value			55.0
Humm Foods [Member]
Cash Flows [Abstract]
Shares issued for acquisition, value			$ 55.0
Shares issued for acquisition, shares			1.8