Property and Equipment, Net - Property and Equipment Table (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 421,170	$ 408,550
Less: Accumulated depreciation	224,080	220,750
Property and equipment, net	197,090	187,800
Land and Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	16,260	15,580
Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	78,690	74,110
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 326,220	$ 318,860

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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