Property and Equipment - Summarized Category of Fixed Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	$ 7,629	$ 7,688
Less accumulated depreciation and amortization	(5,634)	(5,613)
Total property and equipment, net	1,995	2,075
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	5,635	5,635
Right of use, building lease
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	661	720
Computer Equipment and Software
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	437	437
Office Furniture and Equipment
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	174	174
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	43	43
Idle Equipment
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	$ 679	$ 679

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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