Property and Equipment - Summarized Category of Fixed Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	$ 7,732	$ 6,918
Less accumulated depreciation and amortization	(4,019)	(3,846)
Total property and equipment, net	3,713	3,072
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	777	0
Computer Equipment and Software
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	437	406
Office Furniture and Equipment
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	161	155
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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