MORTGAGE SERVICING RIGHTS AND MSR FINANCING RECEIVABLES - Schedule of Advances Included in Servicing Advances Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Schedule of Equity Method Investments [Line Items]
Total	$ 389,905	$ 398,820
Servicer Advances Receivable
Schedule of Equity Method Investments [Line Items]
Principal and interest advances	626,533	664,495
Escrow advances (taxes and insurance advances)	1,234,863	1,426,409
Foreclosure advances	778,880	754,073
Total	2,640,276	2,844,977
Servicer advances receivable related to agency MSRs	508,800	526,500
Servicer advances receivable related to Ginnie Mae MSRS, recoverable from Ginnie Mae	240,200	261,800
Servicer advances, unamortized discount and accrual	$ 46,000	$ 19,500