REAL ESTATE DEBT SECURITIES (Schedule of Activity of Real Estate Securities) (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Held-to-maturity Securities [Roll Forward]
Real estate debt securities - December 31, 2018	$ 13,000,000
Other-than-temporary impairment	0	$ 2,500,000	$ 0
Real estate debt securities - December 31, 2019	0	13,000,000
Debt Securities
Held-to-maturity Securities [Roll Forward]
Real estate debt securities - December 31, 2018	10,859,000
Principal repayment	(7,750,000)
Deferred interest receivable and interest accretion	(2,992,000)
Accretion of commitment fee, net of closing costs	4,000
Held-to-Maturity Securities, Receipt of Deferred Interest Receivable	130,000
Other-than-temporary impairment	9,000
Real estate debt securities - December 31, 2019	$ 0	$ 10,859,000

Held-To-Maturity Securities, Deferred Interest Receivable And Interest Accretion

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- Definition

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

+ References

No definition available.

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

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Held-to-maturity Securities [Roll Forward]

+ References

No definition available.

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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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Amount, before tax, of other-than-temporary impairment (OTTI) on investment in debt security measured at amortized cost (held-to-maturity), recognized in earnings and other comprehensive income (OCI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=118954083&loc=SL6284422-111562

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