FAIR VALUE (Fair Value Measurements By Level 3 Valuation Technique) (Details)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Investments in debt securities	$ 29,645,000	$ 31,365,000
Available-for-sale, Multifamily Tax-exempt, Subordinated Cash Flow Bonds [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	$ 6,114,000	$ 6,026,000
NOI annual growth rate		50.00%
Property bids		$ 50
Available-for-sale, Multifamily Tax-exempt, Subordinated Cash Flow Bonds [Member] \| Measurement Input, Discount Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input	7.2	7.3
Available-for-sale, Multifamily Tax-exempt, Subordinated Cash Flow Bonds [Member] \| Measurement Input, Cap Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input	6.2	6.2
Available-for-sale, Multifamily Tax-exempt, Subordinated Cash Flow Bonds [Member] \| Measurement Input, NOI Annual Growth Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input		0.7
Available-for-sale, Multifamily Tax-exempt, Subordinated Cash Flow Bonds [Member] \| Measurement Input, Contract Price [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input		16,611,000
Available-for-sale, Infrastructure Bonds [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	$ 23,531,000	$ 25,339,000
Available-for-sale, Infrastructure Bonds [Member] \| Measurement Input, Discount Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input	7.8	7.0
Loans Held for Investment
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	$ 1,271,000	$ 500,000
Loans Held for Investment \| Measurement Input, Discount Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Loans receivable, measurement input	8.4	8.0
Weighted Average [Member] \| Loans Held for Investment \| Measurement Input, Discount Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Loans receivable, measurement input		8.0

Fair value inputs, operating income growth rate, percentage weighting factor.

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- Definition

Value of input used to measure fair value of loans receivable.

+ References

No definition available.

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- Definition

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+ References

No definition available.

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- Definition

Amount 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 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Value of input used to measure 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 820
-SubTopic 10
-Section 50
-Paragraph 2
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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.

+ References

No definition available.

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB
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-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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