QUARTERLY FINANCIAL DATA (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended														6 Months Ended		12 Months Ended
	May 29, 2016		Feb. 28, 2016		Nov. 29, 2015		Aug. 30, 2015		May 31, 2015		Feb. 22, 2015		Aug. 24, 2014		Nov. 23, 2014		May 29, 2016	May 31, 2015	May 25, 2014
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 2,827.5		$ 2,924.1		$ 3,095.1		$ 2,796.2		$ 3,125.5		$ 2,907.3		$ 2,765.5		$ 3,138.7		$ 11,642.9	$ 11,937.0	$ 11,838.2
Gross profit	760.9		800.4		828.5		701.0		806.6		720.0		591.3		757.7
Income (loss) from continuing operations, net of tax	(25.1)		187.6		166.1		167.4		234.5		212.3		95.4		218.1		496.0	760.3	625.2
Income (loss) from discontinued operations, net of tax	146.0		18.7		(6.8)		(1,319.8)		(23.0)		(1,165.0)		389.1		(202.2)		(1,161.9)	(1,001.1)	(310.1)
Net income (loss) attributable to ConAgra Foods, Inc.	$ 117.6		$ 204.6		$ 154.9		$ (1,154.1)		$ 209.2		$ (954.1)		$ 482.3		$ 10.0		$ (677.0)	$ (252.6)	$ 303.1
Basic earnings per share:
Net income (loss) attributable to ConAgra Foods, Inc. common stockholders (in dollars per share)	$ 0.27	[1]	$ 0.46	[1]	$ 0.36	[1]	$ (2.68)	[1]	$ 0.49	[1]	$ (2.23)	[1]	$ 1.14	[1]	$ 0.02	[1]	$ (1.57)	$ (0.60)	$ 0.72
Diluted earnings per share:
Net income (loss) attributable to ConAgra Foods, Inc. common stockholders (in dollars per share)	0.27	[1]	0.46	[1]	0.35	[1]	(2.65)	[1]	0.48	[1]	(2.21)	[1]	1.12	[1]	0.02	[1]	(1.56)	(0.59)	0.70
Dividends declared per common share (in dollars per share)	0.25	[1]	0.25	[1]	0.25	[1]	0.25	[1]	0.25	[1]	0.25	[1]	0.25	[1]	0.25	[1]	$ 1.00	$ 1.00	$ 1.00
Share price:
High (in dollars per share)	46.43		42.70		42.75		45.49		38.90		37.29		32.85		35.65
Low (in dollars per share)	$ 42.06		$ 38.70		$ 38.84		$ 37.42		$ 33.58		$ 33.57		$ 28.73		$ 31.87

[1] Basic and diluted earnings per share are calculated independently for each of the quarters presented. Accordingly, the sum of the quarterly earnings per share amounts may not agree with the total year.