Property, Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Property Plant and Equipment [Abstract]
Buildings and Improvements, Gross	$ 46,654	$ 42,353
Construction in-progress	19,468	4,607
Machinery and equipment	410,559	354,008
Property, plant and equipment, gross, total	476,681	400,968
Less: Accumulated depreciation and amortization	(266,228)	(215,213)
Net	210,453	185,755
Land	14,940	14,990
Property, plant and equipment, net, total	225,393	200,745	162,988
Depreciation	$ 56,927	$ 47,365	$ 42,507