Other Financial Statement Details - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 53	$ 105
Less accumulated depreciation and amortization	(31)	(93)
Total	22	12
Computer Hardware [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	52	67
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	$ 1	23
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 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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