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, gross	$ 12,347	$ 12,169
Less accumulated depreciation and amortization	(2,984)	(2,482)
Total	9,363	9,687
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,174	2,007
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	289	289
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,560	1,549
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 8,324	$ 8,324

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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