FAIR VALUE OF FINANCIAL INSTRUMENTS - Unobservable Inputs (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Carrying Amount
Liabilities:
Mortgage payable	$ 97,100	$ 97,100
Junior subordinated notes	27,070	27,070
Carrying Amount \| SBA 7(a) loans receivable, Paycheck Protection Program
Assets:
Loans receivable	4,903	14,089
Carrying Amount \| SBA 7(a) loans receivable, subject to loan-backed notes
Assets:
Loans receivable	18,077	23,606
Carrying Amount \| SBA 7(a) loans receivable, subject to credit risk
Assets:
Loans receivable	42,416	32,509
Carrying Amount \| SBA 7(a) loans receivable, subject to secured borrowings
Assets:
Loans receivable	6,891	8,822
Carrying Amount \| SBA 7(a) loans receivable, held for sale
Assets:
Loans receivable	1,256	4,109
Estimated Fair Value \| Level 2 \| Fair Value, Nonrecurring
Liabilities:
Mortgage payable	100,838	100,799
Estimated Fair Value \| Level 3 \| Fair Value, Nonrecurring
Liabilities:
Mortgage payable	100,838	100,799
Junior subordinated notes	24,378	24,236
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, Paycheck Protection Program \| Fair Value, Nonrecurring
Assets:
Loans receivable	5,050	14,484
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, subject to loan-backed notes \| Fair Value, Nonrecurring
Assets:
Loans receivable	19,635	24,850
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, subject to credit risk \| Fair Value, Nonrecurring
Assets:
Loans receivable	44,399	32,397
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, subject to secured borrowings \| Fair Value, Nonrecurring
Assets:
Loans receivable	6,976	8,914
Estimated Fair Value \| Level 3 \| SBA 7(a) loans receivable, held for sale \| Fair Value, Nonrecurring
Assets:
Loans receivable	$ 1,355	$ 4,527

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

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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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