EARNINGS PER SHARE (Average Share Amounts to Compute EPS) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Aug. 25, 2013	Aug. 26, 2012
Net income available to ConAgra Foods, Inc. common stockholders:
Income from continuing operations attributable to ConAgra Foods, Inc. common stockholders	$ 143.2	$ 250.5
Income (loss) from discontinued operations, net of tax, attributable to ConAgra Foods, Inc. common stockholders	1.1	(0.4)
Net income attributable to ConAgra Foods, Inc.	144.3	250.1
Less: Increase in redemption value of noncontrolling interests in excess of earnings allocated	0.4	0.4
Net income available to ConAgra Foods, Inc. common stockholders	$ 143.9	$ 249.7
Weighted average shares outstanding:
Basic weighted average shares outstanding	421.1	407.1
Add: Dilutive effect of stock options, restricted stock unit awards, and other dilutive securities	7.1	4.9
Diluted weighted average shares outstanding	428.2	412.0