SERVICER ADVANCE INVESTMENTS - Schedule of Interest Income Related to Investments in Servicer Advances - Others' Interests (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Others
Investment [Line Items]
Investment in equity	$ 73,316		$ 73,316		$ 173,057
Ownership interest	27.20%		27.20%		54.20%
Net income	$ 1,224	$ 18,853	$ 10,372	$ 33,400
Others' ownership interest as a percent of total	34.20%	55.50%	50.70%	55.50%
Servicer Advance Joint Venture
Investment [Line Items]
Investment in equity	$ 269,459		$ 269,459		$ 319,248
Ownership interest	72.80%		72.80%
Net income	$ 3,584	$ 33,985	$ 20,460	$ 60,207
Average ownership percentage	65.80%	44.50%	49.30%	44.50%