BUSINESS SEGMENTS AND RELATED INFORMATION (Segment Operations) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Nov. 29, 2015	Nov. 23, 2014	Nov. 29, 2015	Nov. 23, 2014
Net sales
Total net sales	$ 3,092.7	$ 3,136.4	$ 5,886.5	$ 5,899.4
Equity method investment earnings
Total equity method investment earnings	25.3	34.0	62.3	59.6
Operating profit plus equity method investment earnings
Income tax expense	83.2	101.9	168.1	145.0
Income from continuing operations	165.8	218.7	333.0	314.9
Less: Net income attributable to noncontrolling interests	4.4	5.9	6.1	8.1
Income from continuing operations attributable to ConAgra Foods, Inc.	161.4	212.8	326.9	306.8
Reporting segments
Net sales
Total net sales	3,092.7	3,136.4	5,886.5	5,899.4
Operating profit
Total operating profit	493.1	447.7	873.4	759.7
Equity method investment earnings
Total equity method investment earnings	25.3	34.0	62.3	59.6
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	518.4	481.7	935.7	819.3
Segment reconciling items
Operating profit plus equity method investment earnings
General corporate expense	189.8	82.4	274.7	197.4
Interest expense, net	79.6	78.7	159.9	162.0
Income tax expense	83.2	101.9	168.1	145.0
Consumer Foods \| Reporting segments
Net sales
Total net sales	1,983.2	2,043.0	3,676.8	3,742.3
Operating profit
Total operating profit	330.9	300.9	571.5	492.9
Equity method investment earnings
Total equity method investment earnings	0.7	0.8	1.4	1.1
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	331.6	301.7	572.9	494.0
Commercial Foods \| Reporting segments
Net sales
Total net sales	1,109.5	1,093.4	2,209.7	2,157.1
Operating profit
Total operating profit	162.2	146.8	301.9	266.8
Equity method investment earnings
Total equity method investment earnings	24.6	33.2	60.9	58.5
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	$ 186.8	$ 180.0	$ 362.8	$ 325.3

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