Business Segments and Related Information - Segment Operations (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 25, 2012	Nov. 27, 2011	Nov. 25, 2012	Nov. 27, 2011
Net sales
Net sales	$ 3,735.5	$ 3,431.7	$ 7,047.4	$ 6,537.0
Operating profit
Operating profit	455.3	417.1	830.2	710.8
Equity method investment earnings
Equity method investment earnings	12.8	11.5	20.4	17.7
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	468.1	428.6	850.6	728.5
General corporate expenses	89.1	102.0	46.6	206.3
Interest expense, net	53.4	50.6	102.7	103.5
Income tax expense	109.1	92.9	232.6	141.6
Income from continuing operations	216.5	183.1	468.7	277.1
Less: Net income attributable to noncontrolling interests	4.9	2.9	7.0	3.2
Income from continuing operations attributable to ConAgra Foods, Inc.	211.6	180.2	461.7	273.9
Consumer Foods [Member]
Net sales
Net sales	2,423.1	2,178.2	4,465.7	4,069.9
Operating profit
Operating profit	286.0	256.3	521.3	452.5
Equity method investment earnings
Equity method investment earnings	0.5	1.9	0.6	2.9
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	286.5	258.2	521.9	455.4
Commercial Foods [Member]
Net sales
Net sales	1,312.4	1,253.5	2,581.7	2,467.1
Operating profit
Operating profit	169.3	160.8	308.9	258.3
Equity method investment earnings
Equity method investment earnings	12.3	9.6	19.8	14.8
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	$ 181.6	$ 170.4	$ 328.7	$ 273.1

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