REAL ESTATE DEBT SECURITIES - Schedule of Activity of Real Estate Securities (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Held-to-maturity Securities [Roll Forward]
Real estate debt securities - December 31, 2018	$ 13,000
Redemptions of Series B Preferred Units in exchange for Series A-3 Preferred Units	(2,992)	$ 0
Real estate debt securities - September 30, 2019	0
Debt Securities
Held-to-maturity Securities [Roll Forward]
Real estate debt securities - December 31, 2018	10,859
Principal repayment of Series B Preferred Units	(7,750)
Redemptions of Series B Preferred Units in exchange for Series A-3 Preferred Units	(2,992)
Receipt of deferred interest receivable	(130)
Deferred interest receivable	4
Accretion of commitment fee, net of closing costs	9
Real estate debt securities - September 30, 2019	$ 0

Held-to-Maturity Securities, Receipt of Deferred Interest Receivable

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- Definition

Held-to-maturity Securities, Accretion of commitment fee, net of closing costs

+ References

No definition available.

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- Definition

Held-to-maturity Securities, Debt Securities, Face value, Sold

+ References

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- Definition

Held-to-maturity Securities, Deferred interest receivable and interest accretion

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- Definition

Held-to-maturity Securities [Roll Forward]

+ References

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- Definition

Redemption of Held-To-Maturity Securities In Exchange Transaction

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- Definition

Amount of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

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