|
Plant, Property and Equipment - Additional Information (Details) (USD $)
In Millions, unless otherwise specified |
12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2014
|
Dec. 31, 2013
|
Dec. 31, 2012
|
|
| Property, Plant and Equipment [Abstract] | |||
| Depreciation | $ 2.1 | $ 2.6 | $ 3.0 |