EXPENSES, CHANGE IN FAIR VALUE OF INVESTMENTS AND OTHER - Schedule of Accretion and Other Amortization (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Accretion and other amortization:
Accretion of net discount on securities and loans	$ 7,459	$ 3,317	$ 20,971	$ 25,414
Accretion of servicer advances receivable discount and servicer advance investments	515	398	7,371	7,194
Accretion of excess mortgage servicing rights income	7,412	4,195	28,017	16,188
Amortization of deferred financing costs	(4,444)	(2,513)	(9,826)	(10,890)
Total accretion and other amortization	10,498	4,942	45,230	36,559
Secured Notes and Bonds Payable
Accretion and other amortization:
Amortization of discount	0	(14)	0	(14)
Corporate Debt
Accretion and other amortization:
Amortization of discount	$ (444)	$ (441)	$ (1,303)	$ (1,333)