Goodwill and other intangible assets (Idenfitiable Intangible Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Gross carrying amount	$ 19,090	$ 18,920
Accumulated amortization	(8,022)	(7,279)
Intangible assets, net	11,068	11,641
Finite-lived intangible assets:
Gross carrying amount	18,075	17,905
Accumulated amortization	(8,022)	(7,279)
Intangible assets, net	10,053	10,626
IPR&D [Member]
Indefinite-lived intangible assets:
Indefinite-lived intangible assets	1,015	1,015
Developed Product Technology Rights [Member]
Finite-lived intangible assets:
Gross carrying amount	12,313	12,310
Accumulated amortization	(5,472)	(4,996)
Intangible assets, net	6,841	7,314
Licensing Rights [Member]
Finite-lived intangible assets:
Gross carrying amount	3,275	3,275
Accumulated amortization	(1,149)	(998)
Intangible assets, net	2,126	2,277
Research and Development Technology Rights [Member]
Finite-lived intangible assets:
Gross carrying amount	1,138	1,134
Accumulated amortization	(675)	(635)
Intangible assets, net	463	499
Marketing-related Rights [Member]
Finite-lived intangible assets:
Gross carrying amount	1,349	1,186
Accumulated amortization	(726)	(650)
Intangible assets, net	$ 623	$ 536