SERVICER ADVANCE INVESTMENTS - Schedule of Additional Information Regarding the Servicer Advance Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Investments in and Advances to Affiliates [Line Items]
Outstanding Servicer Advances	$ 374,511	$ 376,881
Face Amount of Secured Notes and Bonds Payable	28,627,042
Servicer advance investments | Servicer Advances
Investments in and Advances to Affiliates [Line Items]
UPB of Underlying Residential Mortgage Loans	14,871,701	15,499,559
Outstanding Servicer Advances	$ 313,271	$ 320,630
Servicer Advances to UPB of Underlying Residential Mortgage Loans	2.10%	2.10%
Face Amount of Secured Notes and Bonds Payable	$ 270,705	$ 278,845
Gross Loan-to-Value	84.10%	84.10%
Net Loan-to-Value	81.70%	81.90%
Gross Cost of Funds	7.30%	7.50%
Issue price (as a percent)	6.90%	6.90%