Property, Plant & Equipment, Net - Schedule of Property, Plant & Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	$ 179,713	$ 189,272
Less: accumulated depreciation and amortization	(80,306)	(96,273)
Total property, plant & equipment, net	99,407	92,999
Land
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	13,450	13,450
Buildings
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	63,647	76,059
Machinery, equipment and fixtures
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	68,966	71,870
Construction in progress
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	15,285	7,622
Computer software
Property, Plant & Equipment [Line Items]
Property, plant & equipment, gross	$ 18,365	$ 20,271

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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