Goodwill and acquisition-related intangibles (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Dec. 31, 2011
Goodwill [Line Items]
Goodwill	$ 4,452		$ 4,452
Goodwill, Impairment Loss	0
Finite-Lived Intangible Assets, Net [Abstract]
Acquisition-related intangibles: Gross Carrying Amount	3,054		3,054
Acquisition-related intangibles: Accumulated Amortization	239		154
Acquisition-related intangibles: Net	2,815		2,900
Amortization of acquisition-related intangibles	86
National [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Amortization of acquisition-related intangibles	81
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	2,115		2,089
Acquisition-related intangibles: Accumulated Amortization	148		91
Acquisition-related intangibles: Net	1,967		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
Acquisition-related intangibles: Accumulated Amortization	60		34
Acquisition-related intangibles: Net	762		788
Other Intangibles [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Acquisition-related intangibles: Amortization Period, minimum	2
Acquisition-related intangibles: Amortization Period, maximum	10
Acquisition-related intangibles: Gross Carrying Amount	50		50
Acquisition-related intangibles: Accumulated Amortization	31		29
Acquisition-related intangibles: Net	19		21
In-process R&D [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Acquisition-related intangibles: Gross Carrying Amount	67	[1]	93	[1]
Acquisition-related intangibles: Accumulated Amortization	0	[1]	0	[1]
Acquisition-related intangibles: Net	$ 67	[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.