Certain Balance Sheet Items - Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,302	$ 3,215
Less: Accumulated depreciation and amortization	(2,124)	(1,454)
Property and equipment, net	1,178	1,761
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,429	2,430
Office and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	290	290
Purchased Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	44	44
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 539	$ 451

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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