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 of lessee's right to use underlying asset under finance lease.

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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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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, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Property and Equipment, Net
Finance lease right-of-use assets	$ 435		$ 435		$ 435
Property and equipment, gross	4,891		4,891		4,536
Accumulated depreciation	(2,661)		(2,661)		(2,066)
Property and equipment, net	2,230		2,230		2,470
Depreciation	297	$ 393	595	$ 795
Computer equipment
Property and Equipment, Net
Property and equipment, gross	1,317		1,317		1,315
Lab equipment
Property and Equipment, Net
Property and equipment, gross	1,292		1,292		1,250
Furniture and fixtures
Property and Equipment, Net
Property and equipment, gross	647		647		647
Leasehold improvements
Property and Equipment, Net
Property and equipment, gross	$ 1,200		$ 1,200		$ 889