v2.4.0.8
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, 2013
Dec. 31, 2012
Finite Lived And Indefinite Lived Intangible Assets [Line Items]    
Total finite-lived intangible assets, Gross Amount $ 1,125 $ 909
Accumulated Amortization (291) (251)
Total 834 658
Total indefinite-lived intangible assets, Net Amount 1,575 992
Total Intangible Assets, Gross Amount 2,700 1,901
Total Intangible Assets, Net Amount 2,409 1,650
Exchange and clearing registrations [Member]
    
Finite Lived And Indefinite Lived Intangible Assets [Line Items]    
Total indefinite-lived intangible assets, Net Amount 790 790
Trade Names [Member]
    
Finite Lived And Indefinite Lived Intangible Assets [Line Items]    
Total indefinite-lived intangible assets, Net Amount 760 185
Licenses [Member]
    
Finite Lived And Indefinite Lived Intangible Assets [Line Items]    
Total indefinite-lived intangible assets, Net Amount 51 51
Foreign currency translation adjustment [Member]
    
Finite Lived And Indefinite Lived Intangible Assets [Line Items]    
Total indefinite-lived intangible assets, Net Amount (26) (34)
Technology [Member]
    
Finite Lived And Indefinite Lived Intangible Assets [Line Items]    
Total finite-lived intangible assets, Gross Amount 40 26
Accumulated Amortization (10) (10)
Total 30 16
Total finite-lived intangible assets, Weighted-Average Useful Life (in Years) 5 years 5 years
Customer relationships [Member]
    
Finite Lived And Indefinite Lived Intangible Assets [Line Items]    
Total finite-lived intangible assets, Gross Amount 1,075 871
Accumulated Amortization (278) (238)
Total 797 633
Total finite-lived intangible assets, Weighted-Average Useful Life (in Years) 19 years 21 years
Other [Member]
    
Finite Lived And Indefinite Lived Intangible Assets [Line Items]    
Total finite-lived intangible assets, Gross Amount 6 6
Accumulated Amortization (3) (2)
Total 3 4
Total finite-lived intangible assets, Weighted-Average Useful Life (in Years) 8 years 8 years
Foreign currency translation adjustment [Member]
    
Finite Lived And Indefinite Lived Intangible Assets [Line Items]    
Total finite-lived intangible assets, Gross Amount 4 6
Accumulated Amortization   (1)
Total $ 4 $ 5