Goodwill and acquisition-related intangibles (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011	Sep. 30, 2012		Sep. 30, 2011	Dec. 31, 2011
Goodwill [Line Items]
Goodwill	$ 4,452			$ 4,452			$ 4,452
Goodwill, Impairment Loss				0
Finite-Lived Intangible Assets, Net [Abstract]
Acquisition-related intangibles: Gross Carrying Amount	3,054			3,054			3,054
Acquisition-related intangibles: Accumulated Amortization	411			411			154
Acquisition-related intangibles: Net	2,643			2,643			2,900
Amortization of acquisition-related intangibles	86		12	257		26
National [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Amortization of acquisition-related intangibles	81		6	244		6
Developed Technology [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Acquisition-related intangibles: Amortization Period, minimum				4
Acquisition-related intangibles: Amortization Period, maximum				10
Acquisition-related intangibles: Gross Carrying Amount	2,141			2,141			2,089
Acquisition-related intangibles: Accumulated Amortization	262			262			91
Acquisition-related intangibles: Net	1,879			1,879			1,998
Customer Relationships [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Acquisition-related intangibles: Amortization Period, minimum				5
Acquisition-related intangibles: Amortization Period, maximum				8
Acquisition-related intangibles: Gross Carrying Amount	822			822			822
Acquisition-related intangibles: Accumulated Amortization	112			112			34
Acquisition-related intangibles: Net	710			710			788
Other Intangibles [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Acquisition-related intangibles: Amortization Period, minimum				2
Acquisition-related intangibles: Amortization Period, maximum				7
Acquisition-related intangibles: Gross Carrying Amount	50			50			50
Acquisition-related intangibles: Accumulated Amortization	37			37			29
Acquisition-related intangibles: Net	13			13			21
In-process R&D [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Acquisition-related intangibles: Gross Carrying Amount	41	[1]		41	[1]		93	[1]
Acquisition-related intangibles: Accumulated Amortization	0	[1]		0	[1]		0	[1]
Acquisition-related intangibles: Net	$ 41	[1]		$ 41	[1]		$ 93	[1]

[1] In-process R&D is not amortized until the associated project has been completed, at which point it becomes Developed technology. Alternatively, if the associated project is determined not to be viable, it will be expensed.