Acquisitions (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill	$ 15,675	$ 15,599
Patents and developed technology
Business Acquisition [Line Items]
Acquired intangible assets, weighted-average useful life	4 years 1 month
Customer relationships
Business Acquisition [Line Items]
Acquired intangible assets, weighted-average useful life	4 years
Trade names and other
Business Acquisition [Line Items]
Acquired intangible assets, weighted-average useful life	8 years 3 months 15 days
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Acquisition purchase price	$ 250
Cash acquired	2
Intangible assets	81
Goodwill	135
Net assets acquired	32
Goodwill expected to be tax deductible	$ 18