Goodwill and Other Intangible Assets (Schedule of changes in the carrying amount of goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2020	May 26, 2019	May 27, 2018
Goodwill [Line Items]
Beginning balance	$ 13,995.8	$ 14,065.0	$ 8,747.2
Acquisitions			5,294.9
Divestitures		(0.5)
Purchase accounting adjustment		5.6
Other activity, primarily foreign currency translation	(72.6)	(74.3)	22.9
Ending balance	13,923.2	13,995.8	14,065.0
North America Retail [Member]
Goodwill [Line Items]
Beginning balance	6,406.5	6,410.6	6,406.5
Acquisitions			0.0
Divestitures		0.0
Purchase accounting adjustment		0.0
Other activity, primarily foreign currency translation	(2.8)	(4.1)	4.1
Ending balance	6,403.7	6,406.5	6,410.6
Pet [Member]
Goodwill [Line Items]
Beginning balance	5,300.5	5,294.9	0.0
Acquisitions			5,294.9
Divestitures		0.0
Purchase accounting adjustment		5.6
Other activity, primarily foreign currency translation	0.0	0.0	0.0
Ending balance	5,300.5	5,300.5	5,294.9
Convenience Stores and Foodservice [Member]
Goodwill [Line Items]
Beginning balance	918.8	918.8	918.8
Acquisitions			0.0
Divestitures		0.0
Purchase accounting adjustment		0.0
Other activity, primarily foreign currency translation	0.0	0.0	0.0
Ending balance	918.8	918.8	918.8
Europe and Australia [Member]
Goodwill [Line Items]
Beginning balance	700.4	729.9	700.8
Acquisitions			0.0
Divestitures		0.0
Purchase accounting adjustment		0.0
Other activity, primarily foreign currency translation	(9.7)	(29.5)	29.1
Ending balance	690.7	700.4	729.9
Asia and Latin America [Member]
Goodwill [Line Items]
Beginning balance	260.2	285.0	312.4
Acquisitions			0.0
Divestitures		(0.5)
Purchase accounting adjustment		0.0
Other activity, primarily foreign currency translation	(56.4)	(24.3)	(27.4)
Ending balance	203.8	260.2	285.0
Joint Ventures [Member]
Goodwill [Line Items]
Beginning balance	409.4	425.8	408.7
Acquisitions			0.0
Divestitures		0.0
Purchase accounting adjustment		0.0
Other activity, primarily foreign currency translation	(3.7)	(16.4)	17.1
Ending balance	$ 405.7	$ 409.4	$ 425.8

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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