Property and Equipment, Net - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 105	$ 97
Less accumulated depreciation and amortization	(93)	(74)
Total	12	23
Computer Hardware [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	67	61
Computer Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	23	23
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 13	$ 13

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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