Component of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 5,942	$ 5,300
Less: accumulated depreciation	(4,832)	(4,203)
Property and equipment, net	1,110	1,097
Office and computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	1,436	1,249
Software
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	1,030	1,030
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	1,892	1,839
Research and development equipment
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	1,195	$ 1,182
Capital in-process
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 389

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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