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The amount of identifiable intangible assets recognized as of the acquisition date.

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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 and Divestiture (2012 Acquisition of The Index Business Of Mergent, Inc., Including Indxis) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Purchased goodwill		$ 5,538us-gaap_Goodwill	$ 6,186us-gaap_Goodwill
Index business of Mergent, Inc., Including Indxis [Member]
Business Acquisition [Line Items]
Business acquisition, cash paid	15
Purchased intangible assets	5
Purchased goodwill	9
Net assets acquired	$ 1