v2.4.0.8
Stock-Based Compensation (Stock Based Compensation Textuals) (Details) (USD $)
In Millions, except Share data, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Sep. 30, 2013
Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate     1.40% [1]  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate     25.60% [2]  
Vesting period for graded and cliff vesting options - minimum     1 year  
Vesting period for graded and cliff vesting options - maximum     5 years  
Share-based Compensation Arrangement by Share-based Payment Award, Award Expiration Minimum Range     5 years  
Share-based Compensation Arrangement by Share-based Payment Award, Award Expiration Maximum Range     10 years  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized for Directors 567,000   567,000  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized for Employees 40,533,000   40,533,000  
Percentage of sub-grants representing the total 33.33%   33.33%  
Vest Term of First Sub Grant     1 year  
Vest Term of the Second Sub-Grant     2 years  
Vest Term of the Third Sub-Grant     3 years  
Grants in Option Grants with Three Year Cliff Vesting     1  
Vesting term of option grants with three year cliff vesting     3 years  
Allocated Share-based Compensation Expense $ 8 $ 6 $ 27 $ 19
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value     21 1
Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options     19 4
Liability Classified Share-Based Awards 0   1  
Minimum [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate       1.20%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate       27.00% [2]
Maximum [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate       1.60%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate       30.50% [2]
Stock Options [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized 2   2  
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition     9 months  
Restricted Stock [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized 32   32  
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition     1 year 4 months  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value     21 19
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period     1,770,448  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value     $ 18.46  
Restricted Stock Units (RSUs) [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized $ 1   $ 1  
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition     7 months  
Performance Shares [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period     449,798  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value     $ 21.25  
[1] Zero Coupon U.S. Treasury rate or equivalent based on expected term.
[2] Volatility calculated using the implied volatility of our exchange traded stock options.