Earnings Per Share (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Nov. 27, 2011	Nov. 28, 2010	Nov. 27, 2011	Nov. 28, 2010
Net income available to ConAgra Foods, Inc. common stockholders:
Income from continuing operations attributable to ConAgra Foods, Inc. common stockholders	$ 171.8	$ 200.3	$ 257.0	$ 343.7
Income from discontinued operations, net of tax, attributable to ConAgra Foods, Inc. common stockholders	0	0.6	0.1	3.6
Net income attributable to ConAgra Foods, Inc. common stockholders	171.8	200.9	257.1	347.3
Less: Increase in redemption value of noncontrolling interests in excess of earnings allocated	0.7	0.9	1.0	2.3
Net income available to ConAgra Foods, Inc. common stockholders	$ 171.1	$ 200.0	$ 256.1	$ 345.0
Weighted average shares outstanding:
Basic weighted average shares outstanding	413.6	437.8	413.0	439.7
Add: Dilutive effect of stock options, restricted stock awards, and other dilutive securities	5.0	3.8	5.4	4.1
Diluted weighted average shares outstanding	418.6	441.6	418.4	443.8