Business Segments and Related Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 26, 2012	Feb. 27, 2011	Feb. 26, 2012	Feb. 27, 2011
Net sales
Net sales	$ 3,373.1	$ 3,141.3	$ 9,849.0	$ 9,093.1
Operating profit
Operating profit	481.3	416.6	1,192.1	1,143.3
Equity method investment earnings
Equity method investment earnings	12.6	6.6	30.3	17.4
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	493.9	423.2	1,222.4	1,160.7
General corporate expenses	65.0	23.4	298.5	177.1
Interest expense, net	49.7	51.6	153.2	122.6
Income tax expense	107.0	122.5	238.3	290.8
Income from continuing operations	272.2	225.7	532.4	570.2
Less: Net Income attributable to noncontrolling interests	0.6	0.3	3.8	1.1
Income from continuing operations attributable to ConAgra Foods, Inc.	271.6	225.4	528.6	569.1
Allocation of net derivative gains (losses) from economic hedges of forecasted commodity consumption and foreign currency risk
Net derivative gains (losses) incurred	22.9	25.1	(9.7)	23.9
Net derivative gains (losses) allocated to Reporting Segments	0.9	1.3	29.0	(3.2)
Net derivative gains (losses) recognized in general corporate expenses	22.0	23.8	(38.7)	27.1
Consumer foods [Member]
Net sales
Net sales	2,157.2	2,072.2	6,227.1	5,975.1
Operating profit
Operating profit	331.3	276.0	783.8	762.2
Equity method investment earnings
Equity method investment earnings	1.1	1.6	4.0	4.0
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	332.4	277.6	787.8	766.2
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	2.7	2.6	27.5	(1.1)
Commercial foods [Member]
Net sales
Net sales	1,215.9	1,069.1	3,621.9	3,118.0
Operating profit
Operating profit	150.0	140.6	408.3	381.1
Equity method investment earnings
Equity method investment earnings	11.5	5.0	26.3	13.4
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	161.5	145.6	434.6	394.5
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	$ (1.8)	$ (1.3)	$ 1.5	$ (2.1)