BUSINESS SEGMENTS AND RELATED INFORMATION - Schedule of Segment Operations (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Nov. 26, 2017	Nov. 27, 2016	Nov. 26, 2017	Nov. 27, 2016
Net sales
Total net sales	$ 2,173.4	$ 2,088.4	$ 3,977.6	$ 3,984.0
Operating profit
Total operating profit	395.9	342.9	716.1	691.4
Equity method investment earnings	20.6	17.2	50.6	30.3
General corporate expense	44.9	113.3	85.1	148.9
Interest expense, net	38.0	54.1	74.4	112.3
Income tax expense	109.5	78.4	229.5	247.6
Income from continuing operations	224.1	114.3	377.7	212.9
Less: Net income attributable to noncontrolling interests of continuing operations	1.0	0.6	1.8	0.8
Income from continuing operations attributable to Conagra Brands, Inc.	223.1	113.7	375.9	212.1
Grocery & Snacks
Net sales
Total net sales	900.4	853.2	1,646.2	1,610.4
Operating profit
Total operating profit	199.8	220.2	376.0	400.7
Refrigerated & Frozen
Net sales
Total net sales	758.1	740.7	1,373.8	1,345.3
Operating profit
Total operating profit	128.5	118.0	230.4	210.2
International
Net sales
Total net sales	220.3	211.4	411.2	406.1
Operating profit
Total operating profit	20.2	(26.7)	39.1	(175.9)
Foodservice
Net sales
Total net sales	294.6	283.1	546.4	551.1
Operating profit
Total operating profit	47.4	31.9	70.6	53.6
Commercial
Net sales
Total net sales	0.0	0.0	0.0	71.1
Operating profit
Total operating profit	$ 0.0	$ (0.5)	$ 0.0	$ 202.8

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