ACQUISITIONS (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended				3 Months Ended	12 Months Ended
	Oct. 26, 2018	Feb. 28, 2018	Oct. 31, 2017	Apr. 30, 2017	Sep. 30, 2016	Nov. 25, 2018	May 26, 2019	May 27, 2018	May 28, 2017
Business Acquisition [Line Items]
Cash payment for acquisition, net of cash acquired							$ 5,119.2	$ 337.1	$ 325.7
Aggregate principal amount issued							10,722.0	3,526.4
Issuance of Conagra Brands, Inc. common shares, net							555.7	0.0	0.0
Increase to goodwill							1.5	(1.5)
Net sales							319.1	214.3	36.5
Non-recurring expense related to inventory fair value adjustments							53.0
Classified as goodwill							11,499.6	4,487.4	$ 4,280.8
Pinnacle Foods Inc. (Pinnacle)
Business Acquisition [Line Items]
Amount of cash each share of common stock acquired is convertible into (usd per share)	$ 43.11
Number of shares of stock each share of common stock acquired is convertible into (shares)	0.6494
Par value of shares into which each common stock acquired is convertible into (usd per share)	$ 5.00
Consideration paid in connection with acquisition	$ 8,030.0
Cash payments made in connection with acquisition	5,170.0
Cash payment for acquisition, net of cash acquired	5,120.0
Company shares issues out of treasury (shares)						77,500,000
Value of company shares issued out of treasury in connection with acquisition	2,820.0
Replacement awards to be issued to former employees of acquired entity	51.1
Issuance of Conagra Brands, Inc. common shares, net						$ 555.7
Increase to goodwill							353.9
Reduction in value of brands, trademarks and other intangibles							355.6
Reduction in property, plant and equipment							20.8
Reduction in deferred tax liabilities							32.3
Goodwill deductible for income tax purposes	236.7
Classified as amortizing intangible asset	$ 668.7
Weighted average useful life	25 years
Net sales							1,730.0
Operating profit							238.2
Acquisition-related costs							66.8	62.7
Non-recurring expense related to inventory fair value adjustments								$ 54.1
Non-recurring expense related to securing bridge financing							$ 45.7
Classified as goodwill	$ 7,015.9
Sandwich Bros. of Wisconsin
Business Acquisition [Line Items]
Cash payment for acquisition, net of cash acquired		$ 87.3
Classified as amortizing intangible asset		7.1
Classified as goodwill		57.8
Classified as non-amortizing intangible assets		$ 9.7
Angie's Artisan Treats, LLC
Business Acquisition [Line Items]
Cash payment for acquisition, net of cash acquired			$ 249.8
Goodwill deductible for income tax purposes			95.4
Classified as amortizing intangible asset			10.3
Classified as goodwill			156.7
Classified as non-amortizing intangible assets			$ 73.8
Thanasi Foods, LLC and BIGS LLC
Business Acquisition [Line Items]
Cash payment for acquisition, net of cash acquired				$ 217.6
Goodwill deductible for income tax purposes				70.5
Classified as amortizing intangible asset				16.1
Classified as goodwill				133.3
Classified as non-amortizing intangible assets				$ 65.1
Frontera Foods, Inc. and Red Fork LLC
Business Acquisition [Line Items]
Cash payment for acquisition, net of cash acquired					$ 108.1
Classified as amortizing intangible asset					7.2
Classified as goodwill					39.5
Classified as non-amortizing intangible assets					$ 59.5
Underwritten Public Offering
Business Acquisition [Line Items]
Aggregate principal amount issued						8,330.0
Cash proceeds received from issuance of common stock						575.0
Issuance of Conagra Brands, Inc. common shares, net						$ 555.7