Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property, plant and equipment, net
Property and equipment, gross	$ 14,639	$ 12,732
Less: accumulated depreciation	(5,644)	(5,211)
Property and equipment, net	8,995	7,521
Computer equipment and software
Property, plant and equipment, net
Property and equipment, gross	1,637	1,637
Furniture and fixtures
Property, plant and equipment, net
Property and equipment, gross	1,681	1,737
Leasehold improvements
Property, plant and equipment, net
Property and equipment, gross	4,859	2,938
Laboratory and production equipment
Property, plant and equipment, net
Property and equipment, gross	6,397	6,000
Construction in progress
Property, plant and equipment, net
Property and equipment, gross	$ 65	$ 420

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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