Note 19 - Business Segments and Related Information - Segment Reporting Information by Segment (Details) - USD ($) $ in Millions	12 Months Ended
	May 29, 2022	May 30, 2021	May 31, 2020
Net sales	$ 11,535.9	$ 11,184.7	$ 11,054.4
Operating profit	1,587.6	2,141.0	1,815.6
Equity method investment earnings	145.3	84.4	73.2
General corporate expenses	241.6	364.8	368.5
Pension and postretirement non-service income	(67.3)	(54.5)	(9.9)
Interest expense, net	(379.9)	(420.4)	(487.1)
Income tax expense	290.5	193.8	201.3
Net income	888.2	1,300.9	841.8
Less: Net income attributable to noncontrolling interests	0.0	2.1	1.7
Net income attributable to Conagra Brands, Inc.	888.2	1,298.8	840.1
Grocery And Snacks [Member]
Net sales	4,697.4	4,624.7	4,600.6
Operating profit	859.5	1,092.7	914.3
Refrigerated And Frozen [Member]
Net sales	4,859.3	4,774.6	4,559.6
Operating profit	561.1	836.5	702.2
International [Member]
Net sales	970.8	938.6	925.3
Operating profit	106.7	131.8	100.6
Foodservice [Member]
Net sales	1,008.4	846.8	968.9
Operating profit	60.3	80.0	98.5
Frozen [Member]
Net sales	4,091.1	3,948.0	3,735.5
Other Shelf-stable [Member]
Net sales	2,729.5	2,830.2	2,892.4
Refrigerated [Member]
Net sales	768.2	826.6	824.1
Snacks [Member]
Net sales	1,967.9	1,794.5	1,708.2
International [Member]
Net sales	970.8	938.6	925.3
Foodservice [Member]
Net sales	$ 1,008.4	$ 846.8	$ 968.9