Balance Sheet Components - Components of Property and Equipment - Net (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 2,466	$ 2,344
Less: accumulated depreciation	(1,731)	(1,631)
Total property and equipment – net	735	713
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,336	2,224
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	94	84
Furniture
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 36	$ 36

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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