Acquisitions, West Africa Investments, Goodwill and Other Intangible Assets Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017
Goodwill [Roll Forward]
Goodwill	$ 5,504	$ 5,166
Goodwill Additions	616	375
Goodwill, purchase price allocation adjustment	(2)	(79)
Goodwill, Purchase Accounting Adjustments	0	(4)
Goodwill, Currency Translation Adjustments	(68)	46
Goodwill	6,050	5,504
U.S. Snacks
Goodwill [Roll Forward]
Goodwill	3,568	3,568
Goodwill Additions	0	0
Goodwill, purchase price allocation adjustment	0	0
Goodwill, Purchase Accounting Adjustments	0	0
Goodwill, Currency Translation Adjustments	0	0
Goodwill	3,568	3,568
U.S. Morning Foods
Goodwill [Roll Forward]
Goodwill	131	131
Goodwill Additions	0	0
Goodwill, purchase price allocation adjustment	0	0
Goodwill, Purchase Accounting Adjustments	0	0
Goodwill, Currency Translation Adjustments	0	0
Goodwill	131	131
U.S. Specialty
Goodwill [Roll Forward]
Goodwill	82	82
Goodwill Additions	0	0
Goodwill, purchase price allocation adjustment	0	0
Goodwill, Purchase Accounting Adjustments	0	0
Goodwill, Currency Translation Adjustments	0	0
Goodwill	82	82
North America Other
Goodwill [Roll Forward]
Goodwill	836	457
Goodwill Additions	0	375
Goodwill, purchase price allocation adjustment	(2)	0
Goodwill, Purchase Accounting Adjustments	0	0
Goodwill, Currency Translation Adjustments	(4)	4
Goodwill	830	836
Europe
Goodwill [Roll Forward]
Goodwill	414	376
Goodwill Additions	0	0
Goodwill, purchase price allocation adjustment	0	0
Goodwill, Purchase Accounting Adjustments	0	0
Goodwill, Currency Translation Adjustments	(22)	38
Goodwill	392	414
Latin America
Goodwill [Roll Forward]
Goodwill	244	328
Goodwill Additions	0	0
Goodwill, purchase price allocation adjustment	0	(79)
Goodwill, Purchase Accounting Adjustments	0	(4)
Goodwill, Currency Translation Adjustments	(26)	(1)
Goodwill	218	244
Asia Pacific
Goodwill [Roll Forward]
Goodwill	229	224
Goodwill Additions	616	0
Goodwill, purchase price allocation adjustment	0	0
Goodwill, Purchase Accounting Adjustments	0	0
Goodwill, Currency Translation Adjustments	(16)	5
Goodwill	$ 829	$ 229

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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