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Amount of restructuring charges, remediation cost, and asset impairment loss.

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Business Segment Information (Schedule of operating segment results) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	May 31, 2020	Feb. 23, 2020	Nov. 24, 2019	Aug. 25, 2019	May 26, 2019	Feb. 24, 2019	Nov. 25, 2018	Aug. 26, 2018	May 31, 2020	May 26, 2019	May 27, 2018
Segment Reporting Information [Line Items]
Net sales	$ 5,023.0	$ 4,180.3	$ 4,420.8	$ 4,002.5	$ 4,161.7	$ 4,198.3	$ 4,411.2	$ 4,094.0	$ 17,626.6	$ 16,865.2	$ 15,740.4
Operating profit									2,953.9	2,515.9	2,419.9
Divestitures loss (gain)									0.0	30.0	0.0
Restructuring, impairment, and other exit costs									24.4	275.1	165.6
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									17,626.6	16,865.2	15,740.4
Operating profit									3,487.4	3,160.8	2,791.7
Unallocated Corporate Items [Member]
Segment Reporting Information [Line Items]
Operating profit									509.1	339.8	206.2
Significant Reconciling Items [Member]
Segment Reporting Information [Line Items]
Divestitures loss (gain)									0.0	30.0	0.0
Restructuring, impairment, and other exit costs									24.4	275.1	165.6
North America Retail [Member]
Segment Reporting Information [Line Items]
Net sales									10,750.5	9,925.2	10,115.4
North America Retail [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									10,750.5	9,925.2	10,115.4
Operating profit									2,627.0	2,277.2	2,217.4
U.S. Meals & Baking [Member]
Segment Reporting Information [Line Items]
Net sales									4,408.5	3,839.8	3,865.7
U.S. Cereal [Member]
Segment Reporting Information [Line Items]
Net sales									2,434.1	2,255.4	2,251.8
U.S. Snacks [Member]
Segment Reporting Information [Line Items]
Net sales									2,091.9	2,060.9	2,140.5
U.S. Yogurt & Other [Member]
Segment Reporting Information [Line Items]
Net sales									919.0	906.7	927.4
Canada [Member]
Segment Reporting Information [Line Items]
Net sales									897.0	862.4	930.0
Europe and Australia [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									1,838.9	1,886.7	1,984.6
Operating profit									113.8	123.3	142.1
Convenience Stores and Foodservice [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									1,816.4	1,969.1	1,930.2
Operating profit									337.2	419.5	392.6
Pet Segment [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									1,694.6	1,430.9	0.0
Operating profit									390.7	268.4	0.0
Asia and Latin America [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									1,526.2	1,653.3	1,710.2
Operating profit									$ 18.7	$ 72.4	$ 39.6