Goodwill and other intangible assets (Identifiable Intangible Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Finite-lived intangible assets:
Gross carrying amount	$ 18,307	$ 18,264
Accumulated amortization	(9,506)	(8,744)
Intangible assets, net	8,801	9,520
Indefinite-lived intangible assets:
Gross carrying amount	19,067	19,023
Accumulated amortization	(9,506)	(8,744)
Intangible assets, net	9,561	10,279
IPR&D [Member]
Indefinite-lived intangible assets:
Indefinite-lived intangible assets	760	759
Developed Product Technology Rights [Member]
Finite-lived intangible assets:
Gross carrying amount	12,562	12,534
Accumulated amortization	(6,436)	(5,947)
Intangible assets, net	6,126	6,587
Licensing Rights [Member]
Finite-lived intangible assets:
Gross carrying amount	3,274	3,275
Accumulated amortization	(1,450)	(1,300)
Intangible assets, net	1,824	1,975
Marketing-Related Intangible Assets [Member]
Finite-lived intangible assets:
Gross carrying amount	1,326	1,333
Accumulated amortization	(865)	(793)
Intangible assets, net	461	540
Research and Development Technology Rights [Member]
Finite-lived intangible assets:
Gross carrying amount	1,145	1,122
Accumulated amortization	(755)	(704)
Intangible assets, net	$ 390	$ 418