Share-Based Compensation (Summary of Share-Based Compensation Expense) (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Share-Based Compensation [Abstract] | |||
| Share-based compensation expense before income taxes | $ 68 | $ 62 | $ 47 |
| Income tax benefit | (28) | (26) | (19) |
| Share-based compensation expense after income taxes | $ 40 | $ 36 | $ 28 |
| X | ||||||||||
- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of other income tax expense (benefit). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|