Segments of Business and Geographic Areas - Operating Profit by Segment of Business (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Percentage Change In Sales By Geographic Area	1.90%		0.20%
Sales to customers	$ 20,729	$ 20,348	$ 61,312	$ 61,187
Percentage Change in Operating Income Loss	(62.80%)		(11.90%)
Earnings before provision for taxes on income	$ 1,647	4,423	$ 13,110	14,877
In-process research and development	0	1,126	890	1,126
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability			(129)	162
Restructuring charges	69	88	162	187
CONSUMER
Segment Reporting Information [Line Items]
Sales to customers	3,469	3,415	10,331	10,317
Restructuring charges			100
Litigation expense			200
PHARMACEUTICAL
Segment Reporting Information [Line Items]
Sales to customers	10,877	10,346	31,650	30,544
In-process research and development		1,100	900	1,100
Restructuring charges			100
Litigation expense	4,000		4,300
Research and Development Expense			300
Medical Devices
Segment Reporting Information [Line Items]
Sales to customers	6,383	6,587	19,331	20,326
Restructuring charges	100	200	200	400
Litigation expense			300	700
Operating Segments
Segment Reporting Information [Line Items]
Total Segment Operating Income	$ 1,823	4,653	$ 13,664	15,722
Percentage Change in Operating Income Loss	(60.80%)		(13.10%)
Operating Segments \| CONSUMER
Segment Reporting Information [Line Items]
Total Segment Operating Income	$ 653	510	$ 1,800	1,887
Percentage Change in Operating Income Loss	28.00%		(4.60%)
Amortization	$ 100	100	$ 300	200
Gain (Loss) on Disposition of Assets				300
Operating Segments \| PHARMACEUTICAL
Segment Reporting Information [Line Items]
Total Segment Operating Income	(222)	2,876	$ 5,786	10,193
Percentage Change in Operating Income Loss			(43.20%)
Amortization	800	700	$ 2,400	2,300
Gain (Loss) on Disposition of Assets				100
Unrealized Gain (Loss) on Securities	(100)		200
Operating Segments \| Medical Devices
Segment Reporting Information [Line Items]
Total Segment Operating Income	$ 1,392	1,267	$ 6,078	3,642
Percentage Change in Operating Income Loss	9.90%		66.90%
Amortization	$ 200	300	$ 700	800
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Total Segment Operating Income	$ 176	230	554	845
Ci:z Holdings Co. Ltd. \| CONSUMER
Segment Reporting Information [Line Items]
Gain on sale of equity investments			300
Actelion \| PHARMACEUTICAL
Segment Reporting Information [Line Items]
Acquisition related costs			$ 100	200
XO1 [Member] \| PHARMACEUTICAL
Segment Reporting Information [Line Items]
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability		200		(200)
United States
Segment Reporting Information [Line Items]
Percentage Change In Sales By Geographic Area	1.20%		0.20%
Sales to customers	$ 10,791	10,664	$ 31,323	31,255
United States \| CONSUMER
Segment Reporting Information [Line Items]
Sales to customers	1,394	1,370	4,369	4,282
United States \| PHARMACEUTICAL
Segment Reporting Information [Line Items]
Sales to customers	6,340	6,097	17,705	17,350
United States \| Medical Devices
Segment Reporting Information [Line Items]
Sales to customers	$ 3,057	3,197	$ 9,249	9,623
Europe
Segment Reporting Information [Line Items]
Percentage Change In Sales By Geographic Area	1.00%		(1.60%)
Sales to customers	$ 4,461	4,416	$ 13,803	14,023
Western Hemisphere, excluding U.S.
Segment Reporting Information [Line Items]
Percentage Change In Sales By Geographic Area	(4.00%)		(4.50%)
Sales to customers	$ 1,488	1,550	$ 4,446	4,657
Asia-Pacific, Africa
Segment Reporting Information [Line Items]
Percentage Change In Sales By Geographic Area	7.30%		4.30%
Sales to customers	$ 3,989	$ 3,718	$ 11,740	$ 11,252
ADVANCED \| Operating Segments \| Medical Devices
Segment Reporting Information [Line Items]
Gain (Loss) on Disposition of Business			$ 2,000

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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