|
Changes in Estimates (Details) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
|
Sep. 30, 2014
|
Sep. 30, 2013
|
Sep. 30, 2014
|
Sep. 30, 2013
|
|
| Changes in Estimates (Details) [Abstract] | ||||
| Increase in Operating Income Due to Aggregate Net Changes in Contract Estimates | $ 23 | $ 16 | $ 38 | $ 49 |
| Cummulative operating income adjustment on CRS contract | $ 12 | $ 12 | ||
| Estimated profit margin on CRS contract minimum | 5.50% | 5.50% | ||
| Estimated profit margin on CRS contract maximum | 6.25% | 6.25% | ||