Document and Entity Information	3 Months Ended
Aug. 28, 2016 shares
Document and Entity Information [Abstract]
Entity Registrant Name	CONAGRA FOODS INC /DE/
Entity Central Index Key	0000023217
Current Fiscal Year End Date	--05-28
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Aug. 28, 2016
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding	437,769,664

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