Property and Equipment, Net - Components of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 16,349	$ 16,185
Less: Accumulated depreciation and amortization	(6,118)	(5,679)
Total property and equipment, net	10,231	10,506
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	575	575
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	305	305
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	8,077	7,898
Office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	339	339
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 7,053	$ 7,068

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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