Acquisitions, West Africa Investments, Goodwill and Other Intangible Assets - Intangible Assets Not Subject to Amortization (Details) $ in Millions	9 Months Ended
	Sep. 29, 2018 USD ($)
Indefinite-lived Intangible Assets [Roll Forward]
Intangible assets not subject to amortization, beginning balance	$ 2,505
Additions	373
Currency translation adjustment	(34)
Intangible assets not subject to amortization, ending balance	2,844
U.S. Snacks
Indefinite-lived Intangible Assets [Roll Forward]
Intangible assets not subject to amortization, beginning balance	1,625
Additions	0
Currency translation adjustment	0
Intangible assets not subject to amortization, ending balance	1,625
U.S. Morning Foods
Indefinite-lived Intangible Assets [Roll Forward]
Intangible assets not subject to amortization, beginning balance	0
Additions	0
Currency translation adjustment	0
Intangible assets not subject to amortization, ending balance	0
U.S. Specialty Channels
Indefinite-lived Intangible Assets [Roll Forward]
Intangible assets not subject to amortization, beginning balance	0
Additions	0
Currency translation adjustment	0
Intangible assets not subject to amortization, ending balance	0
North America Other
Indefinite-lived Intangible Assets [Roll Forward]
Intangible assets not subject to amortization, beginning balance	360
Additions	0
Currency translation adjustment	0
Intangible assets not subject to amortization, ending balance	360
Europe
Indefinite-lived Intangible Assets [Roll Forward]
Intangible assets not subject to amortization, beginning balance	434
Additions	0
Currency translation adjustment	(13)
Intangible assets not subject to amortization, ending balance	421
Latin America
Indefinite-lived Intangible Assets [Roll Forward]
Intangible assets not subject to amortization, beginning balance	86
Additions	0
Currency translation adjustment	(16)
Intangible assets not subject to amortization, ending balance	70
Asia Pacific
Indefinite-lived Intangible Assets [Roll Forward]
Intangible assets not subject to amortization, beginning balance	0
Additions	373
Currency translation adjustment	(5)
Intangible assets not subject to amortization, ending balance	$ 368