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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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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Property and Equipment - Summarized Category of Fixed Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	$ 7,804		$ 6,918
Less accumulated depreciation and amortization	(3,852)		(3,846)
Total property and equipment, net	3,952	$ 4,011	3,072
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	5,635		5,635
Right of use, building lease [Member]
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	886
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	406		406
Office Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	155		155
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	43		43
Idle Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant & equipment, gross	$ 679		$ 679