Business Segments and Related Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Nov. 27, 2011	Nov. 28, 2010	Nov. 27, 2011	Nov. 28, 2010
Net sales
Net sales	$ 3,403.9	$ 3,147.5	$ 6,475.9	$ 5,951.8
Operating profit
Operating profit	417.1	405.9	710.8	726.7
Equity method investment earnings
Equity method investment earnings	11.5	4.6	17.7	10.8
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	428.6	410.5	728.5	737.5
General corporate expenses	115.6	74.2	233.5	153.7
Interest expense, net	50.6	33.7	103.5	71.0
Income tax expense	87.7	101.4	131.3	168.3
Income from continuing operations	174.7	201.2	260.2	344.5
Less: Net Income attributable to noncontrolling interests	2.9	0.9	3.2	0.8
Income from continuing operations attributable to ConAgra Foods, Inc.	171.8	200.3	257.0	343.7
Allocation of net derivative gains (losses) from economic hedges of forecasted commodity consumption and foreign currency risk
Net derivative gains (losses) incurred	(20.2)	6.6	(32.6)	(1.2)
Net derivative gains (losses) allocated to Reporting Segments	7.0	(2.5)	28.1	(4.5)
Net derivative gains (losses) recognized in general corporate expenses	(27.2)	9.1	(60.7)	3.3
Consumer Foods [Member]
Net sales
Net sales	2,178.2	2,091.4	4,069.9	3,902.9
Operating profit
Operating profit	256.3	278.5	452.5	486.2
Equity method investment earnings
Equity method investment earnings	1.9	1.3	2.9	2.4
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	258.2	279.8	455.4	488.6
Allocation of net derivative gains (losses) from economic hedges of forecasted commodity consumption and foreign currency risk
Net derivative gains (losses) allocated to Reporting Segments	6.7	(1.9)	24.8	(3.7)
Commercial Foods [Member]
Net sales
Net sales	1,225.7	1,056.1	2,406.0	2,048.9
Operating profit
Operating profit	160.8	127.4	258.3	240.5
Equity method investment earnings
Equity method investment earnings	9.6	3.3	14.8	8.4
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	170.4	130.7	273.1	248.9
Allocation of net derivative gains (losses) from economic hedges of forecasted commodity consumption and foreign currency risk
Net derivative gains (losses) allocated to Reporting Segments	$ 0.3	$ (0.6)	$ 3.3	$ (0.8)