Acquisitions and Divestitures (Schedule Of Acquisition) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Jun. 28, 2013 eSpeed [Member]	May 31, 2013 TR Businesses [Member]
Business Acquisition [Line Items]
Purchase consideration			$ 1,239	$ 366
Net assets acquired			5	(37)
Purchased Intangible Assets			715	91
Goodwill	$ 6,173	$ 6,186	$ 519	$ 312

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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)

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

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-Section 45

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