Intangible Assets and Goodwill - Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Jan. 01, 2017
Goodwill [Roll Forward]
Goodwill beginning of period	$ 22,805	$ 21,629
Goodwill, related to acquisitions	8,463	1,572
Goodwill, related to divestitures	(177)	(75)
Currency translation/other	815	(321)
Goodwill end of period	31,906	22,805
Consumer
Goodwill [Roll Forward]
Goodwill beginning of period	8,263	7,240
Goodwill, related to acquisitions	102	1,362
Goodwill, related to divestitures	(74)	(63)
Currency translation/other	584	(276)
Goodwill end of period	8,875	8,263
Pharmaceutical
Goodwill [Roll Forward]
Goodwill beginning of period	2,840	2,889
Goodwill, related to acquisitions	6,161	0
Goodwill, related to divestitures	(1)	(12)
Currency translation/other	109	(37)
Goodwill end of period	9,109	2,840
Medical Devices
Goodwill [Roll Forward]
Goodwill beginning of period	11,702	11,500
Goodwill, related to acquisitions	2,200	210
Goodwill, related to divestitures	(102)	0
Currency translation/other	122	(8)
Goodwill end of period	$ 13,922	$ 11,702

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 increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of divestiture 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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