v2.4.0.6

Acquisitions and Divestitures (Narrative) (Details) In Millions, unless otherwise specified						1 Months Ended
	May 31, 2012 USD ($)	Dec. 31, 2012 NOS Clearing [Member] USD ($)		Jul. 31, 2012 NOS Clearing [Member] USD ($)	Jul. 31, 2012 NOS Clearing [Member] NOK	May 31, 2012 BWise [Member] USD ($)	May 31, 2012 BWise [Member] EUR (€)	Mar. 31, 2013 BWise [Member]	Dec. 31, 2012 BWise [Member] USD ($)	May 31, 2012 BWise [Member] Customer relationships [Member] USD ($)	May 31, 2012 BWise [Member] Technology [Member] USD ($)	May 31, 2012 BWise [Member] Trade Names [Member] USD ($)	Dec. 31, 2012 Index business of Mergent, Inc., Including Indxis [Member] USD ($)	Dec. 31, 2012 Investor Relations, Public Relations and Multimedia Solutions Businesses of Thomson Reuters [Member] USD ($)	Apr. 30, 2013 TOM [Member]	Apr. 30, 2013 eSpeed [Member]
Business Acquisition [Line Items]
Purchase consideration		$ 40	[1]	$ 40	233	$ 77	€ 62		$ 77					$ 390
Total Net Assets (liabilities) Acquired		43	[1]	43		(11)			(11)				1
Purchased Intangible Assets	35	1	[1]	1		35			35	23	7	5	5
Percentage of acquired ownership interest						72.00%	72.00%								25.00%	100.00%
Percentage of remaining ownership interest						28.00%	28.00%
Percentage of total ownership interest by the first half of 2015								100.00%
Business acquisition, cash paid						57	47						15
Net liabiilties assumed						2
Acquisition recorded as current deferred tax liability						1
Acquisition recorded as non-current deferred tax liability						8
Acquisition recorded as deferred tax liability	9.0					9.0
Purchased intangible assets, tax basis						0
Effective income tax rate						25.00%	25.00%
Purchased goodwill									$ 53				$ 9
[1] In the third quarter of 2012, we recognized a gain of $4 million on our acquisition of NOS Clearing.

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