INVESTMENTS IN RESIDENTIAL MORTGAGE LOANS - Schedule of Real Estate Owned (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Real Estate Owned [Roll Forward]
Beginning balance	$ 128,295	$ 59,591
Purchases	33,377	38,127
Transfer of loans to real estate owned	107,577	124,013
Sales	(152,725)	(95,456)
Valuation provision on REO	3,114	2,020
Ending balance	$ 113,410	$ 128,295

Value transferred from mortgage loans to real estate owned (REO) in noncash transactions.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
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