EARNINGS PER SHARE (Average Share Amounts to Compute EPS) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 22, 2015	Feb. 23, 2014	Feb. 22, 2015	Feb. 23, 2014
Net income (loss) available to ConAgra Foods, Inc. common stockholders:
Income (loss) from continuing operations attributable to ConAgra Foods, Inc. common stockholders	$ (953.5)	$ 223.5	$ (823.8)	$ 560.7
Income (loss) from discontinued operations, net of tax, attributable to ConAgra Foods, Inc. common stockholders	(0.6)	10.8	362.0	66.6
Net income (loss) attributable to ConAgra Foods, Inc.	(954.1)	234.3	(461.8)	627.3
Less: Increase in redemption value of noncontrolling interests in excess of earnings allocated	0.4	0.5	1.3	1.3
Net income (loss) available to ConAgra Foods, Inc. common stockholders	$ (954.5)	$ 233.8	$ (463.1)	$ 626.0
Weighted average shares outstanding:
Basic weighted average shares outstanding	427.1	421.2	425.5	421.1
Add: Dilutive effect of stock options, restricted stock unit awards, and other dilutive securities	0	6.1	0	6.3
Diluted weighted average shares outstanding	427.1	427.3	425.5	427.4