Balance Sheet Components - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Property and equipment	$ 28,276	$ 23,680
Less: Accumulated depreciation	(8,475)	(7,937)
Property and equipment, net	19,801	15,743
Scientific Equipment
Property Plant And Equipment [Line Items]
Property and equipment	12,430	10,642
Furniture and Equipment
Property Plant And Equipment [Line Items]
Property and equipment	3,185	2,572
Capitalized Software
Property Plant And Equipment [Line Items]
Property and equipment	389	389
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment	12,272	509
Property and equipment, net	$ 10,600
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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