Consolidated Statements of Operations - USD ($) $ in Millions	12 Months Ended
	May 28, 2017	May 29, 2016	May 31, 2015
Income Statement [Abstract]
Net sales	$ 7,826.9	$ 8,664.1	$ 9,034.0
Costs and expenses:
Cost of goods sold	5,484.8	6,234.9	6,737.8
Selling, general and administrative expenses	1,417.1	2,024.6	1,383.4
Interest expense, net	195.5	295.8	328.2
Income from continuing operations before income taxes and equity method investment earnings	729.5	108.8	584.6
Income tax expense	254.7	46.4	212.7
Equity method investment earnings	71.2	66.1	79.4
Income from continuing operations	546.0	128.5	451.3
Income (loss) from discontinued operations, net of tax	102.0	(794.4)	(692.1)
Net income (loss)	648.0	(665.9)	(240.8)
Less: Net income attributable to noncontrolling interests	8.7	11.1	11.8
Net income (loss) attributable to Conagra Brands, Inc.	$ 639.3	$ (677.0)	$ (252.6)
Earnings (loss) per share — basic
Income from continuing operations attributable to Conagra Brands, Inc. common stockholders (in dollars per share)	$ 1.26	$ 0.29	$ 1.05
Income (loss) from discontinued operations attributable to Conagra Brands, Inc. common stockholders (in dollars per share)	0.22	(1.86)	(1.65)
Net income (loss) attributable to Conagra Brands, Inc. common stockholders (in dollars per share)	1.48	(1.57)	(0.60)
Earnings (loss) per share — diluted
Income from continuing operations attributable to Conagra Brands, Inc. common stockholders (in dollars per share)	1.25	0.29	1.04
Income (loss) from discontinued operations attributable to Conagra Brands, Inc. common stockholders (in dollars per share)	0.21	(1.85)	(1.63)
Net income (loss) attributable to Conagra Brands, Inc. common stockholders (in dollars per share)	$ 1.46	$ (1.56)	$ (0.59)