|
Employee Benefit Plans (Details) (USD $)
In Millions, unless otherwise specified |
12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2014
|
Dec. 31, 2013
|
Dec. 31, 2012
|
|
| Employee Benefit Plans [Abstract] | |||
| Defined Benefit Plan, Contributions by Employer | $ 27 | $ 24 | $ 19 |