Goodwill and other intangible assets (Identifiable Intangible Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Finite-lived intangible assets:
Gross carrying amounts	$ 18,811	$ 18,344
Accumulated amortization	(10,754)	(10,121)
Intangible assets, net	8,057	8,223
Indefinite-lived intangible assets:
Gross carrying amount	19,197	18,730
Accumulated amortization	(10,754)	(10,121)
Intangible assets, net	8,443	8,609
In-process Research and Development [Member]
Indefinite-lived intangible assets:
Indefinite-lived intangible assets	386	386
Developed-Product-Technology Rights [Member]
Finite-lived intangible assets:
Gross carrying amounts	12,581	12,589
Accumulated amortization	(7,139)	(6,796)
Intangible assets, net	5,442	5,793
Licensing Rights [Member]
Finite-lived intangible assets:
Gross carrying amounts	3,772	3,275
Accumulated amortization	(1,810)	(1,601)
Intangible assets, net	1,962	1,674
Marketing-Related Intangible Assets [Member]
Finite-lived intangible assets:
Gross carrying amounts	1,303	1,319
Accumulated amortization	(967)	(920)
Intangible assets, net	336	399
R&D Technology Rights [Member]
Finite-lived intangible assets:
Gross carrying amounts	1,155	1,161
Accumulated amortization	(838)	(804)
Intangible assets, net	$ 317	$ 357

Identifiable intangible assets accumulated amortization.

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- Definition

Identifiable intangible assets gross.

+ References

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 2
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
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-Paragraph 2
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