THE FREMF TRUSTS - Narrative (Details) - FREMF Trusts - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Variable Interest Entity [Line Items]
Investment in Multi-Family MBS, carrying value	$ 5,331,931	$ 5,331,931	$ 21,695,098
Multi-family mortgage loans held in securitization trusts, unpaid principal balance		27,410,393	1,078,622,737
Multi-family securitized debt obligations, unpaid principal balance		27,410,393	$ 1,078,622,737
Realized losses	$ 13,617	$ 18,325

Amount of net carrying value or investment of Multi-Family Mortgage Backed Securities (MBS) as of balance sheet date.

No definition available.

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- Definition

Amount of unpaid principal balance of multi-family loans held in securitization trusts as of balance sheet date.

+ References

No definition available.

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- Definition

Amount of unpaid principal balance of multi-family securitized debt obligations as of balance sheet date.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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