Balance Sheets Components - Schedule of Property and Equipment Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 32,399	$ 28,088
Accumulated depreciation	(17,472)	(16,380)
Total property and equipment, net	14,927	11,708
Lab and Manufacturing Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	26,020	21,958
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,199	1,121
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	249	237
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	638	638
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 4,293	$ 4,134

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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