Property and Equipment, net - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 7,294	$ 6,267
Less: Accumulated depreciation	(3,150)	(2,188)
Total property and equipment, net	4,144	4,079
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Total property and equipment, gross	22	22
Laboratory Equipment
Property Plant And Equipment [Line Items]
Total property and equipment, gross	6,251	5,580
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total property and equipment, gross	701	657
Construction in Progress
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 320	$ 8

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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