INVESTMENTS IN DEBT SECURITIES (Bonds and Related Unrealized Gains and Losses) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Fair Value	$ 29,645	$ 31,365
Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unpaid principal balance of bond investments	30,885	30,885
Amortized Cost	20,840	20,797
Gross Unrealized Gains	8,805	10,568
Fair Value	$ 29,645	$ 31,365
FV as a % of UPB	96.00%	102.00%
Multifamily Tax-Exempt Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Unpaid principal balance of bond investments	$ 4,000	$ 4,000
Gross Unrealized Gains	6,114	6,026
Fair Value	$ 6,114	$ 6,026
FV as a % of UPB	153.00%	151.00%
Infrastructure Bond [Member]
Schedule of Available-for-sale Securities [Line Items]
Unpaid principal balance of bond investments	$ 26,885	$ 26,885
Amortized Cost	20,840	20,797
Gross Unrealized Gains	2,691	4,542
Fair Value	$ 23,531	$ 25,339
FV as a % of UPB	88.00%	94.00%

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Unpaid principal balance of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

No definition available.

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- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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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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