BUSINESS SEGMENTS AND RELATED INFORMATION (Segment Operations) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 23, 2014	Nov. 24, 2013	Nov. 23, 2014	Nov. 24, 2013
Net sales
Net sales	$ 4,150.0us-gaap_SalesRevenueGoodsNet	$ 4,221.1us-gaap_SalesRevenueGoodsNet	$ 7,851.0us-gaap_SalesRevenueGoodsNet	$ 7,936.9us-gaap_SalesRevenueGoodsNet
Operating profit (loss)
Total operating profit	247.5us-gaap_OperatingIncomeLoss	503.4us-gaap_OperatingIncomeLoss	600.5us-gaap_OperatingIncomeLoss	871.0us-gaap_OperatingIncomeLoss
Equity method investment earnings
Total equity method investment earnings	34.0	5.2	59.6	9.3
Operating profit (loss) plus equity method investment earnings
Total operating profit plus equity method investment earnings	281.5	508.6	660.1	880.3
Interest expense, net	79.3us-gaap_InterestExpense	95.5us-gaap_InterestExpense	163.0us-gaap_InterestExpense	191.3us-gaap_InterestExpense
Income tax expense	84.0us-gaap_IncomeTaxExpenseBenefit	106.0us-gaap_IncomeTaxExpenseBenefit	126.5us-gaap_IncomeTaxExpenseBenefit	134.9us-gaap_IncomeTaxExpenseBenefit
Income from continuing operations	26.6	210.4	137.8	343.8
Less: Net income attributable to noncontrolling interests	5.9	3.7	8.1	6.6
Income from continuing operations attributable to ConAgra Foods, Inc.	20.7	206.7	129.7	337.2
Consumer Foods
Net sales
Net sales	1,977.2	2,016.3	3,609.5	3,665.7
Operating profit (loss)
Total operating profit	301.7	285.9	491.7	450.9
Equity method investment earnings
Total equity method investment earnings	0.8	0.5	1.1	0.9
Operating profit (loss) plus equity method investment earnings
Total operating profit plus equity method investment earnings	302.5	286.4	492.8	451.8
Commercial Foods
Net sales
Net sales	1,120.8	1,099.8	2,209.1	2,168.7
Operating profit (loss)
Total operating profit	148.1	127.7	269.2	264.8
Equity method investment earnings
Total equity method investment earnings	33.2	4.7	58.5	8.4
Operating profit (loss) plus equity method investment earnings
Total operating profit plus equity method investment earnings	181.3	132.4	327.7	273.2
Private Brands
Net sales
Net sales	1,052.0	1,105.0	2,032.4	2,102.5
Operating profit (loss)
Total operating profit	(202.3)	89.8	(160.4)	155.3
Operating profit (loss) plus equity method investment earnings
Total operating profit plus equity method investment earnings	(202.3)	89.8	(160.4)	155.3
General corporate expense
Operating profit (loss) plus equity method investment earnings
General corporate expense	$ 91.6	$ 96.7	$ 232.8	$ 210.3

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