Segment and Geographic Area Information - Depreciation and Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Information
Depreciation	$ 1,195	$ 1,078	$ 1,100
Additions to Property and Equipment	2,193	1,668	1,394
Total Assets	72,548	67,887	67,173
Segment assets:
Total Assets	72,548	67,887	67,173
Other
Segment Information
Depreciation	195	172	167
Additions to Property and Equipment	218	160	160
Total Reportable Segment Operating Earnings
Segment Information
Depreciation	1,000	906	933
Additions to Property and Equipment	1,975	1,508	1,234
Total Assets	20,955	18,007	16,085
Segment assets:
Total Assets	20,955	18,007	16,085
Total Reportable Segment Operating Earnings | Established Pharmaceutical Products
Segment Information
Depreciation	88	98	92
Additions to Property and Equipment	109	109	131
Total Assets	2,888	2,858	2,664
Segment assets:
Total Assets	2,888	2,858	2,664
Total Reportable Segment Operating Earnings | Nutritional Products
Segment Information
Depreciation	143	139	150
Additions to Property and Equipment	201	141	86
Total Assets	3,478	3,274	3,071
Segment assets:
Total Assets	3,478	3,274	3,071
Total Reportable Segment Operating Earnings | Diagnostic Products
Segment Information
Depreciation	488	403	397
Additions to Property and Equipment	1,263	726	609
Total Assets	7,696	5,235	4,464
Segment assets:
Total Assets	7,696	5,235	4,464
Total Reportable Segment Operating Earnings | Medical Devices
Segment Information
Depreciation	281	266	294
Additions to Property and Equipment	402	532	408
Total Assets	6,893	6,640	5,886
Segment assets:
Total Assets	6,893	6,640	5,886
Reconciling items
Segment assets:
Cash and investments	7,969	5,023	4,983
Goodwill and intangible assets	38,528	40,220	42,196
All other	$ 5,096	$ 4,637	$ 3,909