Property, Plant and Equipment, Net - Schedule of Property, Plant & Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	$ 197,420	$ 190,627
Less: accumulated depreciation and amortization	(85,209)	(82,739)
Total property, plant and equipment, net	112,211	107,888
Land
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	13,450	13,450
Buildings
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	64,957	64,444
Machinery, equipment and fixtures
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	70,133	69,298
Computer software
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	19,846	19,266
Construction in progress
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	$ 29,034	$ 24,169

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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