EXCESS MORTGAGE SERVICING RIGHTS - Schedule of Carrying Value of Investments in Excess MSRs (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2024 USD ($)
Carrying Value of Investments in Excess MSRs
Beginning balance	$ 8,405,938
Servicing Asset, Fair Value, Change in Fair Value, Other, Statement of Income or Comprehensive Income [Extensible Enumeration]	Realized and unrealized gains (losses), net
Ending balance	$ 9,693,331
Excess MSRs
Carrying Value of Investments in Excess MSRs
Beginning balance	208,385
Purchases	122,887
Interest income	10,522
Other income	(656)
Proceeds from repayments	(19,122)
Proceeds from sales	0
Change in fair value	19,430
Acquisition of assets from Fortress Excess MSR JV	55,192
Reclassification of SLS serviced Excess MSRs to Full MSRs	1,032
Ending balance	$ 395,606