Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Property and Equipment, Net
Property and equipment, gross	$ 7,729	$ 5,546
Less: Accumulated depreciation and amortization	(3,558)	(2,356)
Total property and equipment, net	4,171	3,190
Depreciation and amortization expense	1,303	807
Laboratory equipment
Property and Equipment, Net
Property and equipment, gross	5,432	3,585
Leasehold improvements
Property and Equipment, Net
Property and equipment, gross	1,580	1,578
Computer equipment & software
Property and Equipment, Net
Property and equipment, gross	423
Furniture & fixtures
Property and Equipment, Net
Property and equipment, gross	219	219
Machinery & equipment
Property and Equipment, Net
Property and equipment, gross	$ 75	75
Construction in progress
Property and Equipment, Net
Property and equipment, gross		$ 89

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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