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Business Segment and Geographic Information (Operating Segment Results) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	May 26, 2024	Feb. 25, 2024	Nov. 26, 2023	Aug. 27, 2023	May 28, 2023	Feb. 26, 2023	Nov. 27, 2022	Aug. 28, 2022	May 26, 2024	May 28, 2023	May 29, 2022
Segment Reporting Information [Line Items]
Net sales	$ 4,713.9	$ 5,099.2	$ 5,139.4	$ 4,904.7	$ 5,030.0	$ 5,125.9	$ 5,220.7	$ 4,717.6	$ 19,857.2	$ 20,094.2	$ 18,992.8
Divestitures gain, net									0.0	444.6	194.1
Restructuring, impairment, and other exit costs (recoveries)									241.4	56.2	(26.5)
Operating profit									3,431.7	3,433.8	3,475.8
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									19,854.4	20,094.2	18,992.8
Operating profit									4,007.0	4,078.6	3,657.8
Unallocated Corporate Items [Member]
Segment Reporting Information [Line Items]
Operating profit									333.9	1,033.2	402.6
Significant Reconciling Items [Member]
Segment Reporting Information [Line Items]
Divestitures gain, net									0.0	444.6	194.1
Restructuring, impairment, and other exit costs (recoveries)									241.4	56.2	(26.5)
North America Retail Segment [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									12,473.4	12,659.9	11,572.0
Operating profit									3,080.4	3,181.3	2,699.7
U.S. Meals & Baking Solutions [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									4,324.3	4,426.3	4,023.8
U.S. Morning Foods [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									3,561.8	3,620.1	3,370.9
U.S. Snacks [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									3,538.9	3,611.0	3,191.4
Canada [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									1,048.4	1,002.5	985.9
International [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									2,746.5	2,769.5	3,315.7
Operating profit									125.2	161.8	232.0
North America Foodservice [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									2,258.7	2,191.5	1,845.7
Operating profit									315.5	290.0	255.5
Pet Segment [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									2,375.8	2,473.3	2,259.4
Operating profit									485.9	445.5	470.6
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Net sales									$ 2.8	$ 0.0	$ 0.0