Property Plant and Equipment - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Building	$ 26,934	$ 26,934
Land	6,683	6,683
Equipment and other	203,017	192,004
Property and equipment, gross	236,634	225,621
Accumulated depreciation	(160,443)	(152,944)
Property and equipment, net	$ 76,191	$ 72,677

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 of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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- Definition

Amount before accumulated depreciation of fixtures and equipment. Includes, but is not limited to, machinery, equipment, and engines.

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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