Balance Sheet Components - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property and equipment	$ 23,680	$ 11,127
Less: Accumulated depreciation	(7,937)	(5,989)
Property and equipment, net	15,743	5,138
Scientific Equipment
Property Plant And Equipment [Line Items]
Property and equipment	10,642	9,126
Furniture and Equipment
Property Plant And Equipment [Line Items]
Property and equipment	2,572	1,248
Capitalized Software
Property Plant And Equipment [Line Items]
Property and equipment	389	302
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment	509	$ 451
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment	$ 9,568

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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