Identifiable Intangible Assets and Goodwill - Finite-lived and Indefinite-lived Intangible Assets (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets		$ 3,954	$ 4,165
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount		91,903	91,788
Finite-lived intangible assets, accumulated amortization	[1]	(62,833)	(60,743)
Finite-lived intangible assets, net		29,070	31,045
Intangible assets, gross carrying amount	[1]	95,857	95,954
Finite-lived intangible assets, accumulated amortization	[1]	(62,833)	(60,743)
Identifiable Intangible Assets, less Accumulated Amortization	[1],[2]	33,024	35,211
Brands [Member]
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets		1,994	1,994
In Process Research and Development [Member]
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets		1,961	2,171
Developed Technology Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount		89,540	89,430
Finite-lived intangible assets, accumulated amortization		(60,949)	(58,895)
Finite-lived intangible assets, net		28,590	30,535
Finite-lived intangible assets, accumulated amortization		(60,949)	(58,895)
Brands [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount		923	923
Finite-lived intangible assets, accumulated amortization		(725)	(708)
Finite-lived intangible assets, net		198	215
Finite-lived intangible assets, accumulated amortization		(725)	(708)
License Agreements and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount		1,440	1,436
Finite-lived intangible assets, accumulated amortization		(1,159)	(1,140)
Finite-lived intangible assets, net		281	296
Finite-lived intangible assets, accumulated amortization		$ (1,159)	$ (1,140)

[1] The decrease in Identifiable intangible assets, less accumulated amortization, is primarily due to amortization and intangible asset impairment charges, partially offset by additions for the period. See Note 4 for additional information on intangible asset impairments.

[2] Amounts may not add due to rounding.