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Business Segment and Geographic Information (Operating Segment Results) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	May 25, 2025	Feb. 23, 2025	Nov. 24, 2024	Aug. 25, 2024	May 26, 2024	Feb. 25, 2024	Nov. 26, 2023	Aug. 27, 2023	May 25, 2025	May 26, 2024	May 28, 2023
Segment Reporting Information [Line Items]
Net sales	$ 4,556.2	$ 4,842.2	$ 5,240.1	$ 4,848.1	$ 4,713.9	$ 5,099.2	$ 5,139.4	$ 4,904.7	$ 19,486.6	$ 19,857.2	$ 20,094.2
Cost of sales									12,753.6	12,925.1	13,548.4
Selling, general, and administrative expenses									3,445.8	3,259.0	3,500.4
Divestitures gain, net									(95.9)	0.0	(444.6)
Restructuring, transformation, impairment, and other exit costs									78.3	241.4	56.2
Operating profit									3,304.8	3,431.7	3,433.8
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									19,476.5	19,854.4	20,094.2
Operating profit									3,682.7	4,007.0	4,078.6
Corporate and Other Net Sales [Member]
Segment Reporting Information [Line Items]
Net sales									10.1	2.8
Operating profit									395.5	333.9	1,033.2
North America Retail Segment [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									11,907.0	12,473.4	12,659.9
Cost of sales									7,472.1	7,650.8	7,782.2
Selling, general, and administrative expenses									1,705.0	1,742.2	1,696.4
Operating profit									2,729.9	3,080.4	3,181.3
U.S. Meals & Baking Solutions[Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									4,238.9	4,324.3	4,426.3
U.S. Morning Foods [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									3,439.9	3,561.8	3,620.1
U.S. Snacks [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									3,356.3	3,538.9	3,611.0
Canada [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									871.9	1,048.4	1,002.5
International [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									2,797.8	2,746.5	2,769.5
Cost of sales									2,110.6	2,073.4	2,055.2
Selling, general, and administrative expenses									590.8	547.9	552.5
Operating profit									96.4	125.2	161.8
North America Pet Segment [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									2,470.8	2,375.8	2,473.3
Cost of sales									1,476.4	1,446.8	1,611.7
Selling, general, and administrative expenses									493.4	443.1	416.1
Operating profit									501.0	485.9	445.5
North America Foodservice [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									2,300.9	2,258.7	2,191.5
Cost of sales									1,772.9	1,781.9	1,749.5
Selling, general, and administrative expenses									172.6	161.3	152.0
Operating profit									$ 355.4	$ 315.5	$ 290.0