Certain Balance Sheet Accounts - Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Total cost	$ 11,040	$ 10,764
Less accumulated depreciation and amortization	(9,548)	(9,033)
Total property and equipment, net	1,492	1,731
Depreciation and amortization	952	1,386	$ 1,616
Equipment under finance leases
Property, Plant and Equipment [Line Items]
Total cost	6,204	5,979
Laboratory equipment
Property, Plant and Equipment [Line Items]
Total cost	3,135	3,091
Computer equipment
Property, Plant and Equipment [Line Items]
Total cost	1,076	1,069
Office equipment and furniture
Property, Plant and Equipment [Line Items]
Total cost	$ 625	$ 625

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Amount of accumulated depreciation and amortization from plant, property, and equipment and right-of-use asset from finance lease.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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