Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 321,407	$ 314,200
Accumulated depreciation	(170,009)	(162,912)
Property, plant and equipment, Net	151,398	151,288
Land and Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	5,167	5,122
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	44,084	44,116
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	258,916	250,936
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	4,381	5,315
Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 8,859	$ 8,711