Property and Equipment - Composition of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 4,650	$ 3,883
Less accumulated depreciation	(2,013)	(1,959)
Property and equipment, net	2,637	1,924
Lab equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,185	2,112
Computer hardware, software and telephone
Property, Plant and Equipment [Line Items]
Property and equipment, gross	279	279
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	107	107
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	67	67
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,012	$ 1,318

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.

+ References

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