Property and Equipment, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 122,142	$ 126,099
Less accumulated depreciation	(95,364)	(100,497)
Total property and equipment, net	26,778	25,602
Land
Property Plant And Equipment [Line Items]
Property and equipment - gross	875	875
Buildings
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 17,389	17,389
Buildings \| Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	39 years
Buildings \| Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	40 years
Building Improvements
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 37,543	34,967
Building Improvements \| Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	5 years
Building Improvements \| Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	40 years
Machinery and Equipment
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 54,982	61,217
Machinery and Equipment \| Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	3 years
Machinery and Equipment \| Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	15 years
Furniture, fixtures and office equipment
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 3,005	2,954
Furniture, fixtures and office equipment \| Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	5 years
Furniture, fixtures and office equipment \| Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	10 years
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 8,234	8,355
Estimated Useful Life (Years)	3 years
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 114	$ 342

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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