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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Property and equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Property and equipment, net
Property and equipment, gross	$ 4,367		$ 4,367		$ 3,751
Less: Accumulated depreciation and amortization	(2,365)		(2,365)		(1,933)
Property and equipment, net	2,002		2,002		1,818
Depreciation expense	200	$ 200	400	$ 400
Laboratory equipment
Property and equipment, net
Property and equipment, gross	3,884		3,884		3,356
Leasehold improvements
Property and equipment, net
Property and equipment, gross	142		142		75
Computer equipment and software
Property and equipment, net
Property and equipment, gross	225		225		221
Furniture and office equipment
Property and equipment, net
Property and equipment, gross	$ 116		$ 116		$ 99