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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity.

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Amount of assets acquired at the acquisition date.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Acquisitions/Divestitures - Purchase Price Allocation (Details) - USD ($) $ in Millions			9 Months Ended
	Apr. 08, 2016	Jan. 29, 2016	Sep. 30, 2016	Dec. 31, 2015	Dec. 31, 2014
Acquisitions:
Goodwill			$ 36,401	$ 32,021	$ 30,556
Completed technology \| Minimum
Acquisitions:
Acquired intangible asset, weighted average useful life			1 year
Completed technology \| Maximum
Acquisitions:
Acquired intangible asset, weighted average useful life			7 years
Client relationships \| Minimum
Acquisitions:
Acquired intangible asset, weighted average useful life			3 years
Client relationships \| Maximum
Acquisitions:
Acquired intangible asset, weighted average useful life			7 years
Patents/trademarks \| Minimum
Acquisitions:
Acquired intangible asset, weighted average useful life			2 years
Patents/trademarks \| Maximum
Acquisitions:
Acquired intangible asset, weighted average useful life			7 years
The Weather Company
Acquisitions:
Current assets		$ 76
Fixed assets/noncurrent assets		123
Goodwill		1,717
Total assets acquired		2,738
Current liabilities		(88)
Noncurrent liabilities		(372)
Total liabilities assumed		(460)
Total purchase price		$ 2,278
Acquired intangible asset, weighted average useful life		6 years 10 months 24 days
The Weather Company \| Completed technology
Acquisitions:
Intangible assets		$ 160
The Weather Company \| Client relationships
Acquisitions:
Intangible assets		313
The Weather Company \| Patents/trademarks
Acquisitions:
Intangible assets		$ 349
Truven Health Analytics
Acquisitions:
Current assets	$ 171
Fixed assets/noncurrent assets	127
Goodwill	1,933
Total assets acquired	3,141
Current liabilities	(148)
Noncurrent liabilities	(381)
Total liabilities assumed	(529)
Total purchase price	$ 2,612
Acquired intangible asset, weighted average useful life	6 years 10 months 24 days
Truven Health Analytics \| Completed technology
Acquisitions:
Intangible assets	$ 338
Truven Health Analytics \| Client relationships
Acquisitions:
Intangible assets	516
Truven Health Analytics \| Patents/trademarks
Acquisitions:
Intangible assets	$ 54
Other Acquisitions
Acquisitions:
Current assets			$ 78
Fixed assets/noncurrent assets			89
Goodwill			487
Total assets acquired			947
Current liabilities			(46)
Noncurrent liabilities			(64)
Total liabilities assumed			(110)
Bargain purchase gain			(40)
Total purchase price			$ 798
Acquired intangible asset, weighted average useful life			6 years 4 months 24 days
Other Acquisitions \| Completed technology
Acquisitions:
Intangible assets			$ 75
Other Acquisitions \| Client relationships
Acquisitions:
Intangible assets			189
Other Acquisitions \| Patents/trademarks
Acquisitions:
Intangible assets			$ 28