Property and Equipment, net - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 45,995	$ 46,880
Less: accumulated depreciation	(8,558)	(7,326)
Property and equipment, net	37,437	39,554
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	36,116	37,130
Office furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,861	4,963
Computer hardware
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,618	3,365
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,352	1,350
Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 48	$ 72