EARNINGS PER SHARE - Reconciliation of Income and Average Share Amounts Used to Compute Basic and Diluted Earnings Per Share (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended						9 Months Ended
	Feb. 27, 2022	Nov. 28, 2021	Aug. 29, 2021	Feb. 28, 2021	Nov. 29, 2020	Aug. 30, 2020	Feb. 27, 2022	Feb. 28, 2021
Earnings Per Share [Abstract]
Net income attributable to Conagra Brands, Inc. common stockholders:	$ 218.4	$ 275.5	$ 235.4	$ 281.4	$ 378.9	$ 329.0	$ 729.3	$ 989.3
Weighted average shares outstanding:
Basic weighted average shares outstanding	480.3			485.7			480.3	487.4
Add: Dilutive effect of stock options, restricted stock unit awards, and other dilutive securities	1.9			1.9			1.9	1.8
Diluted weighted average shares outstanding	482.2			487.6			482.2	489.2