Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 9,010		$ 8,458
Less: accumulated depreciation and amortization	(6,539)		(6,343)
Property and equipment, net	2,471		2,115
Depreciation and amortization, property and equipment	200	$ 200
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,234		4,225
Equipment and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 4,776		$ 4,233

Depreciation And Amortization, Property, Plant, And Equipment

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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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