BUSINESS SEGMENTS AND RELATED INFORMATION (Segment Operations) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Feb. 28, 2016	Feb. 22, 2015	Feb. 28, 2016	Feb. 22, 2015
Net sales
Total net sales	$ 2,924.1	$ 2,907.3	$ 8,815.4	$ 8,811.5
Equity method investment earnings
Total equity method investment earnings	44.7	33.0	107.0	92.6
Operating profit plus equity method investment earnings
Income tax expense	91.0	100.6	259.3	247.9
Income from continuing operations	187.6	212.3	521.1	525.8
Less: Net income attributable to noncontrolling interests	1.7	1.4	7.8	9.5
Income from continuing operations attributable to ConAgra Foods, Inc.	185.9	210.9	513.3	516.3
Reporting segments
Net sales
Total net sales	2,924.1	2,907.3	8,815.4	8,811.5
Operating profit
Total operating profit	466.3	410.5	1,335.5	1,171.1
Equity method investment earnings
Total equity method investment earnings	44.7	33.0	107.0	92.6
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	511.0	443.5	1,442.5	1,263.7
Segment reconciling items
Operating profit plus equity method investment earnings
General corporate expense	155.5	50.8	425.3	248.2
Interest expense, net	76.9	79.8	236.8	241.8
Income tax expense	91.0	100.6	259.3	247.9
Consumer Foods \| Reporting segments
Net sales
Total net sales	1,854.8	1,899.7	5,531.6	5,642.0
Operating profit
Total operating profit	291.3	266.0	857.8	758.9
Equity method investment earnings
Total equity method investment earnings	1.1	1.3	2.5	2.4
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	292.4	267.3	860.3	761.3
Commercial Foods \| Reporting segments
Net sales
Total net sales	1,069.3	1,007.6	3,283.8	3,169.5
Operating profit
Total operating profit	175.0	144.5	477.7	412.2
Equity method investment earnings
Total equity method investment earnings	43.6	31.7	104.5	90.2
Operating profit plus equity method investment earnings
Total operating profit plus equity method investment earnings	$ 218.6	$ 176.2	$ 582.2	$ 502.4

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