SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Estimated Useful Lives and Components of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Total leasehold improvements and equipment	$ 1,311	$ 2,139
Accumulated depreciation and amortization	(704)	(784)
Leasehold improvements and equipment, net	607	1,355
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total leasehold improvements and equipment	$ 761	1,332
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives (in years)	10 years
Computer and other equipment
Property, Plant and Equipment [Line Items]
Total leasehold improvements and equipment	$ 550	$ 807
Computer and other equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives (in years)	2 years
Computer and other equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives (in years)	10 years