THE FREMF TRUSTS - Narrative (Details) - FREMF Trusts - USD ($)	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
Investment in Multi-Family MBS, carrying value	$ 0	$ 4,762,149
Realized losses	$ 709,439

Amount of Net Income (Loss) attributable to noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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