Goodwill And Purchased Intangible Assets (Finite-Lived And Indefinite-Lived Intangible Assets) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Acquired Finite-Lived Intangible Assets [Line Items]
Accumulated Amortization	$ (191)	$ (190)
Total intangible assets, Gross Amount	1,848	1,909
Total intangible assets, Net Assets	1,657	1,719
Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total finite-lived intangible assets, Gross Amount	37	72
Accumulated Amortization	(8)	(41)
Total finite-lived intangible assets, Net Assets	29	31
Total finite-lived intangible assets, Weighted Average Useful Life (in Years)	9	6
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total finite-lived intangible assets, Gross Amount	852	853
Accumulated Amortization	(185)	(152)
Total finite-lived intangible assets, Net Assets	667	701
Total finite-lived intangible assets, Weighted Average Useful Life (in Years)	21	21
Other [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total finite-lived intangible assets, Gross Amount	6	6
Accumulated Amortization	(1)	(1)
Total finite-lived intangible assets, Net Assets	5	5
Total finite-lived intangible assets, Weighted Average Useful Life (in Years)	8	8
Foreign Currency Translation Adjustment [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total finite-lived intangible assets, Gross Amount	(23)	(15)
Accumulated Amortization	3	4
Total finite-lived intangible assets, Net Assets	(20)	(11)
Foreign Currency Translation Adjustment [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total indefinite-lived intangible assets, Gross Amount	(73)	(56)
Total indefinite-lived intangible assets, Net Amount	(73)	(56)
Finite-Lived Intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total finite-lived intangible assets, Gross Amount	872	916
Accumulated Amortization	(191)	(190)
Total finite-lived intangible assets, Net Assets	681	726
Exchange And Clearing Registrations [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total indefinite-lived intangible assets, Gross Amount	790	790
Total indefinite-lived intangible assets, Net Amount	790	790
Trade Names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total indefinite-lived intangible assets, Gross Amount	181	181
Total indefinite-lived intangible assets, Net Amount	181	181
Licenses [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total indefinite-lived intangible assets, Gross Amount	78	78
Total indefinite-lived intangible assets, Net Amount	78	78
Indefinite-Lived Intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Total indefinite-lived intangible assets, Gross Amount	976	993
Total indefinite-lived intangible assets, Net Amount	$ 976	$ 993

Indefinite-Lived Intangible Assets, Gross Carrying Amount

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Total Intangible Assets Gross

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The calculated weighted-average amortization period of a major class of finite-lived intangible assets acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

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The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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

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Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The aggregate sum of gross carrying value of a major finite-lived intangible asset class, less accumulated amortization and any impairment charges. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Sum of the carrying amounts (original costs for current and prior period additions adjusted for impairment, if any) as of the balance sheet date of intangible assets, excluding goodwill, having a projected indefinite period of benefit.

+ References

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

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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

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