FAIR VALUE OF FINANCIAL INSTRUMENTS - Fair Value of Financial Instruments Not Recorded at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Carrying Amount
Liabilities:
Mortgages payable	$ 97,100	$ 97,100
Junior subordinated notes	27,070	27,070
Carrying Amount \| SBA 7(a) loans receivable, subject to credit risk
Assets:
Loans receivable	46,118	42,416
Carrying Amount \| SBA 7(a) loans receivable, subject to loan-backed notes
Assets:
Loans receivable	16,901	18,077
Carrying Amount \| SBA 7(a) loans receivable, paycheck protection program
Assets:
Loans receivable	3,287	4,903
Carrying Amount \| SBA 7(a) loans receivable, subject to secured borrowings
Assets:
Loans receivable	6,491	6,891
Carrying Amount \| SBA 7(a) loans receivable, held for sale
Assets:
Loans receivable	6,607	1,256
Fair Value, Measurements, Nonrecurring \| Estimated Fair Value \| Level 3
Liabilities:
Mortgages payable	96,030	100,838
Junior subordinated notes	24,518	24,378
Fair Value, Measurements, Nonrecurring \| Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, subject to credit risk
Assets:
Loans receivable	47,726	44,399
Fair Value, Measurements, Nonrecurring \| Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, subject to loan-backed notes
Assets:
Loans receivable	18,380	19,635
Fair Value, Measurements, Nonrecurring \| Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, paycheck protection program
Assets:
Loans receivable	3,387	5,050
Fair Value, Measurements, Nonrecurring \| Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, subject to secured borrowings
Assets:
Loans receivable	6,575	6,976
Fair Value, Measurements, Nonrecurring \| Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, held for sale
Assets:
Loans receivable	7,111	1,355
Fair Value, Measurements, Nonrecurring \| Estimated Fair Value \| Level 2
Liabilities:
Mortgages payable	$ 96,030	$ 100,838

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

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-Name Accounting Standards Codification
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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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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.

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