|
Property, plant and equipment (Details) (USD $)
In Thousands, unless otherwise specified |
Mar. 31, 2013
|
Dec. 31, 2012
|
|---|---|---|
| Property, plant and equipment | ||
| Total property, plant and equipment | $ 49,600 | $ 48,820 |
| Less accumulated depreciation | (29,587) | (28,933) |
| Net property, plant and equipment | 20,013 | 19,887 |
|
Land
|
||
| Property, plant and equipment | ||
| Total property, plant and equipment | 960 | 960 |
|
Land improvements
|
||
| Property, plant and equipment | ||
| Total property, plant and equipment | 1,777 | 1,768 |
|
Buildings
|
||
| Property, plant and equipment | ||
| Total property, plant and equipment | 12,852 | 12,852 |
|
Machinery and equipment
|
||
| Property, plant and equipment | ||
| Total property, plant and equipment | 24,314 | 24,286 |
|
Furniture and fixtures
|
||
| Property, plant and equipment | ||
| Total property, plant and equipment | 7,492 | 7,465 |
|
Mobile equipment and other
|
||
| Property, plant and equipment | ||
| Total property, plant and equipment | 1,201 | 1,138 |
|
Construction-in-process
|
||
| Property, plant and equipment | ||
| Total property, plant and equipment | $ 1,004 | $ 351 |