|
Stock-Based Compensation (Narrative) (Details) (USD $)
In Millions, unless otherwise specified |
3 Months Ended |
|---|---|
|
Mar. 31, 2015
|
|
| Share-based Compensation [Abstract] | |
| Unrecognized compensation expense | $ 326 |
| Recognition period | 3 years 4 months 24 days |