SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of investments in the VIE (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Securities and other investments owned, at fair value	$ 1,144,896	$ 1,532,095
Loans receivable, at fair value	770,840	873,186
Other assets	15,244	11,525
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Securities and other investments owned, at fair value	30,968	27,445
Loans receivable, at fair value	76,995	205,265
Other assets	2,855	4,956
Maximum exposure to loss	$ 110,818	$ 237,666