Acquisitions, West Africa Investments, Goodwill and Other Intangible Assets Annual Impairment Testing (Details) - USD ($) $ in Millions	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Indefinite-lived Intangible Assets [Line Items]
Goodwill and other intangible assets	$ 9,400
Other intangible assets excluding goodwill	2,840	$ 2,505	$ 2,282
Goodwill	6,050	5,504	5,166
U.S. Snacks
Indefinite-lived Intangible Assets [Line Items]
Other intangible assets excluding goodwill	$ 1,625	$ 1,625	1,625
Percentage of excess over fair value	62.00%	57.00%
Goodwill	$ 3,568	$ 3,568	$ 3,568
Kashi
Indefinite-lived Intangible Assets [Line Items]
Percentage of excess over fair value	12.00%	9.00%
Goodwill	$ 207
Multipro
Indefinite-lived Intangible Assets [Line Items]
Other intangible assets excluding goodwill	798
Goodwill	616
Keebler and Pringles Trademarks \| U.S. Snacks
Indefinite-lived Intangible Assets [Line Items]
Other intangible assets excluding goodwill	$ 2,800

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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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
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