Composition of Certain Balance Sheet Items - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 3,588	$ 3,528
Less accumulated depreciation	(2,107)	(1,853)
Property and equipment, net of accumulated depreciation	1,481	1,675
Furniture and equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	871	810
Software
Property, Plant and Equipment [Line Items]
Total property and equipment	1,485	1,485
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 1,232	$ 1,233