Note 19 - Business Segments and Related Information - Segment Reporting Information by Segment (Details) - USD ($) $ in Millions	12 Months Ended
	May 28, 2023	May 29, 2022	May 30, 2021
Net sales	$ 12,277.0	$ 11,535.9	$ 11,184.7
Operating profit	1,464.2	1,587.6	2,141.0
Equity method investment earnings	212.0	145.3	84.4
General corporate expenses	388.9	241.6	364.8
Pension and postretirement non-service income	(24.2)	(67.3)	(54.5)
Interest expense, net	(409.6)	(379.9)	(420.4)
Income tax expense	218.7	290.5	193.8
Net income	683.2	888.2	1,300.9
Less: Net income attributable to noncontrolling interests	(0.4)	0.0	2.1
Net income attributable to Conagra Brands, Inc.	683.6	888.2	1,298.8
Grocery And Snacks [Member]
Net sales	4,981.9	4,697.4	4,624.7
Operating profit	1,002.8	859.5	1,092.7
Refrigerated And Frozen [Member]
Net sales	5,156.2	4,859.3	4,774.6
Operating profit	255.0	561.1	836.5
International [Member]
Net sales	1,002.5	970.8	938.6
Operating profit	121.4	106.7	131.8
Foodservice [Member]
Net sales	1,136.4	1,008.4	846.8
Operating profit	85.0	60.3	80.0
Frozen [Member]
Net sales	4,288.1	4,091.1	3,948.0
Other Shelf-stable [Member]
Net sales	2,851.9	2,729.5	2,830.2
Refrigerated [Member]
Net sales	868.1	768.2	826.6
Snacks [Member]
Net sales	2,130.0	1,967.9	1,794.5
International [Member]
Net sales	1,002.5	970.8	938.6
Foodservice [Member]
Net sales	$ 1,136.4	$ 1,008.4	$ 846.8