v2.4.0.8
Share-Based Compensation (Summary of Share-Based Compensation Expense) (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Share-Based Compensation [Abstract]    
Share-based compensation expense before income taxes $ 14 $ 9
Income tax benefit (6) (4)
Share-based compensation expense after income taxes $ 8 $ 5