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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Acquisitions/Divestitures (Purchase Price allocation) (Details 2) - USD ($) $ in Millions		9 Months Ended
	Oct. 13, 2015	Sep. 30, 2015	Dec. 31, 2014	Dec. 31, 2013
Acquisitions:
Goodwill		$ 30,275	$ 30,556	$ 31,184
Business enterprise value		782
Acquisitions
Acquisitions:
Current assets		20
Fixed assets/noncurrent assets		63
Goodwill		637
Total assets acquired		851
Current liabilities		(16)
Noncurrent liabilities		(53)
Total liabilities assumed		(70)
Total purchase price		$ 782
Acquired intangible asset, weighted average useful life		5 years 10 months
Acquisitions \| Completed technology
Acquisitions:
Intangible assets		$ 79
Acquisitions \| Completed technology \| Minimum
Acquisitions:
Acquired intangible asset, weighted average useful life		5 years
Acquisitions \| Completed technology \| Maximum
Acquisitions:
Acquired intangible asset, weighted average useful life		7 years
Acquisitions \| Client relationships
Acquisitions:
Intangible assets		$ 41
Acquired intangible asset, weighted average useful life		7 years
Acquisitions \| Patents/trademarks
Acquisitions:
Intangible assets		$ 12
Acquisitions \| Patents/trademarks \| Minimum
Acquisitions:
Acquired intangible asset, weighted average useful life		2 years
Acquisitions \| Patents/trademarks \| Maximum
Acquisitions:
Acquired intangible asset, weighted average useful life		5 years
Merge Healthcare Incorporated \| Subsequent event \| Estimated
Acquisitions:
Business enterprise value	$ 1,000