Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property and Equipment
Property and equipment, gross	$ 35,741	$ 34,350
Less accumulated depreciation	(31,364)	(29,687)
Property and equipment, net	4,377	4,663
Depreciation expense	1,783	2,017	$ 2,101
Agreement to liquidate equipment, cost basis			$ 7,500
Accumulated depreciation and impairment charges for liquidated equipment	6,800	1,400
Leasehold improvements
Property and Equipment
Property and equipment, gross	22,867	22,051
Machinery and equipment
Property and Equipment
Property and equipment, gross	3,063	2,955
Computer hardware and software
Property and Equipment
Property and equipment, gross	6,248	5,846
Furniture and fixtures
Property and Equipment
Property and equipment, gross	3,383	3,265
Assets under construction
Property and Equipment
Property and equipment, gross	180	233
Equipment under capital leases
Property and Equipment
Property and equipment, gross	2,200	2,100
Less accumulated depreciation	$ (1,800)	$ (1,600)

Amount of accumulated depreciation, impairment for physical assets liquidated.

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Represents the cost basis to liquidate 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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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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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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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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