FAIR VALUE OF FINANCIAL INSTRUMENTS - Narrative (Details)	Jun. 30, 2020	Dec. 31, 2019
Measurement Input, Discount Rate | Mortgages Payable | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for debt	0.0386	0.0367
Measurement Input, Discount Rate | Junior Subordinated Debt | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for debt	0.0455	0.0616
Measurement Input, Discount Rate | SBA 7(a) loans receivable, subject to credit risk | Minimum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.0425	0.0525
Measurement Input, Discount Rate | SBA 7(a) loans receivable, subject to credit risk | Maximum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.0675	0.0775
Measurement Input, Discount Rate | SBA 7(a) loans receivable, subject to loan-backed notes | Minimum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.0475	0.0525
Measurement Input, Discount Rate | SBA 7(a) loans receivable, subject to loan-backed notes | Maximum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.0625	0.0725
Measurement Input, Discount Rate | SBA 7(a) loans receivable, paycheck protection program | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.0100
Measurement Input, Discount Rate | SBA 7(a) loans receivable, subject to secured borrowings | Minimum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.0575	0.0675
Measurement Input, Discount Rate | SBA 7(a) loans receivable, subject to secured borrowings | Maximum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.0600	0.0750
Measurement Input, Prepayment Rate | SBA 7(a) loans receivable, subject to credit risk | Minimum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.0985	0.0985
Measurement Input, Prepayment Rate | SBA 7(a) loans receivable, subject to credit risk | Maximum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.1750	0.1750
Measurement Input, Prepayment Rate | SBA 7(a) loans receivable, subject to loan-backed notes | Minimum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.1341	0.1341
Measurement Input, Prepayment Rate | SBA 7(a) loans receivable, subject to loan-backed notes | Maximum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.1680	0.1680
Measurement Input, Prepayment Rate | SBA 7(a) loans receivable, subject to secured borrowings | Minimum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.1177	0.1177
Measurement Input, Prepayment Rate | SBA 7(a) loans receivable, subject to secured borrowings | Maximum | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input for loans receivable	0.1680	0.1680