Property and Equipment, Net - Property and Equipment Table (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 408,550	$ 392,930
Less: Accumulated depreciation	220,750	202,680
Property and equipment, net	187,800	190,250
Land and Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	15,580	15,500
Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	74,110	73,550
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 318,860	$ 303,880

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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