Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 74	$ 74
Less accumulated depreciation and amortization	(74)	(74)
Property and equipment-net	0	0
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2	2
Computer and office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	13	13
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 59	$ 59

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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