MORTGAGE SERVICING RIGHTS AND MSR FINANCING RECEIVABLES - Schedule of Advances Included in Servicing Advances Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Transfers and Servicing [Abstract]
Principal and interest advances	$ 583,741	$ 640,723
Escrow advances (taxes and insurance advances)	1,339,713	1,733,426
Foreclosure advances	848,976	950,092
Gross advance balance	2,772,430	3,324,241
Reserves, impairment, unamortized discount, net of recovery accruals	(125,389)	(125,320)
Total	2,647,041	3,198,921
Servicer advances receivable related to agency MSRs	527,500	673,700
Servicer advances receivable related to Ginnie Mae MSRS, recoverable from Ginnie Mae	$ 450,500	$ 529,300