Note 14 - Business Segments and Related Information - Segment Reporting Information by Segment (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Nov. 27, 2022	Aug. 28, 2022	Nov. 28, 2021	Aug. 29, 2021	Nov. 27, 2022	Nov. 28, 2021
Net sales	$ 3,312.9		$ 3,058.9		$ 6,217.2	$ 5,712.2
Operating profit	656.1		468.4		718.3	896.3
Equity method investment earnings	49.3		29.5		98.5	49.7
General corporate expense	106.5		59.0		190.0	123.6
Pension and postretirement non-service income	(6.1)		(16.1)		(12.2)	(32.2)
Interest expense, net	100.3		94.9		197.4	189.1
Income tax expense	122.5		84.2		136.9	153.9
Net income	382.2		275.9		304.7	511.6
Less: Net income attributable to noncontrolling interests	0.3		0.4		0.3	0.7
Net income attributable to Conagra Brands, Inc. common stockholders:	381.9	$ (77.5)	275.5	$ 235.4	304.4	510.9
Grocery And Snacks [Member]
Net sales	1,349.9		1,264.5		2,538.2	2,339.6
Operating profit	340.4		249.2		590.8	465.1
Refrigerated And Frozen [Member]
Net sales	1,421.5		1,285.9		2,629.1	2,387.7
Operating profit	250.3		168.3		34.0	325.9
International [Member]
Net sales	258.7		262.2		492.2	498.8
Operating profit	36.9		37.1		63.8	71.2
Foodservice [Member]
Net sales	282.8		246.3		557.7	486.1
Operating profit	28.5		13.8		29.7	34.1
Frozen [Member]
Net sales	1,157.5		1,073.1		2,165.9	1,993.5
Other Shelf-stable [Member]
Net sales	758.4		724.6		1,448.5	1,366.2
Refrigerated [Member]
Net sales	264.0		212.8		463.2	394.2
Snacks [Member]
Net sales	591.5		539.9		1,089.7	973.4
Foodservice [Member]
Net sales	282.8		246.3		557.7	486.1
International [Member]
Net sales	$ 258.7		$ 262.2		$ 492.2	$ 498.8