FAIR VALUE OF FINANCIAL INSTRUMENTS - Unobservable Inputs (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Estimated Fair Value \| Level 3 \| Fair Value, Nonrecurring
Liabilities:
Mortgage payable (1)	$ 100,799	$ 99,764
Junior subordinated notes (1)	24,236	24,406
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, Paycheck Protection Program \| Fair Value, Nonrecurring
Assets:
Loans receivable	14,484	0
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, subject to loan-backed notes \| Fair Value, Nonrecurring
Assets:
Loans receivable	24,850	30,076
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, subject to credit risk \| Fair Value, Nonrecurring
Assets:
Loans receivable	32,397	28,041
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, subject to secured borrowings \| Fair Value, Nonrecurring
Assets:
Loans receivable	8,914	12,780
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, held for sale \| Fair Value, Nonrecurring
Assets:
Loans receivable	4,527	1,753
Carrying Amount
Liabilities:
Mortgage payable (1)	97,100	97,100
Junior subordinated notes (1)	27,070	27,070
Carrying Amount \| SBA 7(a) loans receivable, Paycheck Protection Program
Assets:
Loans receivable	14,089	0
Carrying Amount \| SBA 7(a) loans receivable, subject to loan-backed notes
Assets:
Loans receivable	23,606	27,595
Carrying Amount \| SBA 7(a) loans receivable, subject to credit risk
Assets:
Loans receivable	32,509	26,149
Carrying Amount \| SBA 7(a) loans receivable, subject to secured borrowings
Assets:
Loans receivable	8,822	12,682
Carrying Amount \| SBA 7(a) loans receivable, held for sale
Assets:
Loans receivable	$ 4,109	$ 1,653

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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