Composition of Other Balance Sheet Items - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property and equipment
Property and equipment, gross	$ 28,935	$ 28,222
Less accumulated depreciation and amortization	(15,405)	(13,049)
Property and equipment, net	13,530	15,173
Depreciation and amortization expense	2,500	3,000	$ 2,600
Lab equipment and furniture
Property and equipment
Property and equipment, gross	13,069	12,127
Leasehold improvements
Property and equipment
Property and equipment, gross	14,023	14,023
Software
Property and equipment
Property and equipment, gross	883	883
Computer equipment
Property and equipment
Property and equipment, gross	960	983
Construction-in-progress
Property and equipment
Property and equipment, gross	$ 0	$ 206

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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