v2.4.0.8
Stock-Based Compensation (Schedule of Non-qualified Stock Option Activity) (Details) (USD $)
In Millions, except Share data, unless otherwise specified
 9 Months Ended 12 Months Ended
Sep. 30, 2014
Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]    
Options, Outstanding 11,196,086 14,114,289
Options, Outstanding, Weighted Average Exercise Price $ 18.79 $ 18.25
Options, Outstanding, Weighted Average Remaining Contractual Term 2 years 3 months 10 days 3 years 1 month 6 days
Options, Outstanding, Intrinsic Value $ 40 $ 36
Options, Grants in Period, Gross 0  
Options, Grants in Period, Weighted Average Exercise Price $ 0.00  
Options, Exercises in Period 2,869,586  
Options, Exercises in Period, Weighted Average Exercise Price $ 16.18  
Options, Forfeitures in Period 46,117  
Options, Forfeitures in Period, Weighted Average Exercise Price $ 16.05  
Options, Expirations in Period 2,500  
Options, Expirations in Period, Weighted Average Exercise Price $ 17.79  
Options, Exercisable 10,423,567  
Options, Exercisable, Weighted Average Exercise Price $ 19.05  
Options, Exercisable, Weighted Average Remaining Contractual Term 1 year 10 months 25 days  
Options, Exercisable, Intrinsic Value 35  
Options, Vested and Expected to Vest, Outstanding 11,175,937  
Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price $ 18.80  
Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term 2 years 3 months 10 days  
Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value $ 40