Property, Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Land and land improvements	$ 19,643	$ 19,643
Buildings and improvements	49,838	49,832
Machinery and equipment	250,042	248,247
Office furniture and equipment	6,493	6,432
Construction in progress	297	1,126
Property, Plant and Equipment, Gross	326,313	325,280
Accumulated depreciation	(116,668)	(89,392)
Property, plant and equipment, net	$ 209,645	$ 235,888