Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 5,562	$ 6,003
Less accumulated depreciation	(4,428)	(4,781)
Property and equipment, net	1,134	1,222
Laboratory equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	4,374	4,836
Computer equipment and software
Property, Plant and Equipment [Line Items]
Total property and equipment	494	515
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	268	278
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property and equipment	219	237
Office equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	78	135
Construction in process
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 129	$ 2