Property, Plant and Equipment, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment
Property, plant and equipment, gross	$ 438,708	$ 438,490
Less accumulated depreciation and amortization	(257,115)	(245,383)
Property, plant and equipment excluding capital projects in progress, net	181,593	193,107
Capital projects in progress	32,123	13,920
Property, plant and equipment, net	213,716	207,027
Original cost of fully depreciated assets still in use	156,700	161,100
Payments to Acquire Manufacturing Facility	12,600
Estimated Building Improvements Minimum	7,000
Estimated Building Improvements Maximum	10,000
Depreciation expense	20,400	20,400	$ 20,100
Land
Property, Plant and Equipment
Property, plant and equipment, gross	28,698	29,390
Buildings and site improvements
Property, Plant and Equipment
Property, plant and equipment, gross	171,890	175,058
Leasehold improvements
Property, Plant and Equipment
Property, plant and equipment, gross	5,560	5,602
Machinery and equipment
Property, Plant and Equipment
Property, plant and equipment, gross	232,560	228,440
Software development
Property, Plant and Equipment
Property, plant and equipment, gross	1,600	1,800
Capital projects in progress	$ 12,200	$ 8,300