SERVICER ADVANCE INVESTMENTS - Schedule of Interest Income Related to Investments in Servicer Advances (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Schedule of Equity Method Investments [Line Items]
Interest income	$ 233,848	$ 448,127	$ 868,419	$ 1,303,041
Servicer Advance Investments
Schedule of Equity Method Investments [Line Items]
Interest income, gross of amounts attributable to servicer compensation	10,505	14,212	28,160	43,220
Amounts attributable to base servicer compensation	(703)	(1,606)	(2,325)	(4,578)
Amounts attributable to incentive servicer compensation	1,196	(7,273)	(12,755)	(20,780)
Interest income	$ 10,998	$ 5,333	$ 13,080	$ 17,862