Document and Entity Information	3 Months Ended
	Aug. 25, 2019 shares
Document And Entity Information [Abstract]
Entity Registrant Name	CONAGRA BRANDS INC.
Entity Central Index Key	0000023217
Current Fiscal Year End Date	--05-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Aug. 25, 2019
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Trading Symbol	CAG
Amendment Flag	false
Entity Common Stock, Shares Outstanding	486,654,153
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Current Reporting Status	Yes
Entity File Number	1-7275
Entity Tax Identification Number	470248710
Entity Address, Address Line One	222 W. Merchandise Mart Plaza
Entity Address, Address Line Two	Suite 1300
Entity Address, City or Town	Chicago
Entity Address, State or Province	Illinois
Entity Address, Postal Zip Code	60654
City Area Code	(312)
Local Phone Number	549-5000