v2.4.0.8

Acquisition and Divestitures (Schedule Of Intangible Assets) (Details) (USD $) In Millions, unless otherwise specified		9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended										9 Months Ended			9 Months Ended		9 Months Ended						0 Months Ended	9 Months Ended	0 Months Ended	9 Months Ended	0 Months Ended	9 Months Ended
	May 31, 2012	Sep. 30, 2013 Technology [Member]	Dec. 31, 2012 Technology [Member]	Sep. 30, 2013 Customer relationships [Member]	Dec. 31, 2012 Customer relationships [Member]	Sep. 30, 2013 Other [Member]	Dec. 31, 2012 Other [Member]	Dec. 31, 2012 NOS Clearing [Member]		Jul. 31, 2012 NOS Clearing [Member]	Dec. 31, 2012 BWise [Member]	May 31, 2012 BWise [Member]	May 31, 2012 BWise [Member] Technology [Member]	May 31, 2012 BWise [Member] Customer relationships [Member]	Sep. 30, 2013 eSpeed [Member]	Jun. 28, 2013 eSpeed [Member]	Sep. 30, 2013 eSpeed [Member] Trade Names [Member]	Sep. 30, 2013 eSpeed [Member] Technology [Member]	Jun. 28, 2013 eSpeed [Member] Technology [Member]	Sep. 30, 2013 eSpeed [Member] Customer relationships [Member]	Jun. 28, 2013 eSpeed [Member] Customer relationships [Member]	Sep. 30, 2013 eSpeed [Member] Market Services [Member] Trade Names [Member]	Sep. 30, 2013 eSpeed [Member] Market Services [Member] Technology [Member]	Sep. 30, 2013 eSpeed [Member] Market Services [Member] Customer relationships [Member]	Sep. 30, 2013 eSpeed [Member] Information Services [Member] Trade Names [Member]	Sep. 30, 2013 eSpeed [Member] Information Services [Member] Technology [Member]	Sep. 30, 2013 eSpeed [Member] Information Services [Member] Customer relationships [Member]	May 31, 2013 TR Businesses [Member]	Sep. 30, 2013 TR Businesses [Member]	May 31, 2013 TR Businesses [Member] Technology [Member]	Sep. 30, 2013 TR Businesses [Member] Technology [Member]	May 31, 2013 TR Businesses [Member] Customer relationships [Member]	Sep. 30, 2013 TR Businesses [Member] Customer relationships [Member]	Sep. 30, 2013 Minimum [Member] TR Businesses [Member] Technology [Member]	Sep. 30, 2013 Minimum [Member] TR Businesses [Member] Customer relationships [Member]	Sep. 30, 2013 Maximum [Member] TR Businesses [Member] Technology [Member]	Sep. 30, 2013 Maximum [Member] TR Businesses [Member] Customer relationships [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Acquired Finite Lived Intangible Assets Weighted Average Useful Life		5 years	5 years	19 years	21 years	8 years	8 years											5 years		13 years			5 years	13 years		5 years	13 years							2 years	9 years	5 years	14 years
Indefinite-lived Intangible Assets Acquired																	$ 578					$ 528			$ 50
Finite-lived Intangible Assets Acquired																		16		121			14	105		2	16	91	91	2	2	89	89
Purchased Intangible Assets	$ 35							$ 1	[1]	$ 1	$ 35	$ 35	$ 7	$ 23	$ 715	$ 715			$ 16		$ 121								$ 91
[1] In the third quarter of 2012, we recognized a gain of $4 million on our acquisition of NOS Clearing, which is included in merger and strategic initiatives expense in the Condensed Consolidated Statements of Income.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472



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Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, resulting from a business combination.

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