SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - USD ($)		3 Months Ended	12 Months Ended
	Feb. 14, 2019	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 15, 2015
Debt and Equity Securities, FV-NI [Line Items]
Maximum exposure to loss from consolidated trusts		$ 4,762,149	$ 0
Nonaccrual status loans			0
Impairments on loans held-for-investments			0
Allowance for loan losses			0
Total Commitment			40,250,000
Accumulated amortization, debt issuance costs			$ 1,017,419
Common stock, shares authorized (in shares)			450,000,000	450,000,000
Common stock, par value (in dollars per share)			$ 0.01	$ 0.01
Common stock, shares issued (in shares)			23,692,164	23,687,664
Common stock, shares outstanding (in shares)			23,692,164	23,687,664
Stock repurchase program, authorized amount					$ 10,000,000
Preferred stock, shares outstanding (in shares)			0	1,610,000
Preferred stock, dividend rate (percentage)			8.75%	8.75%
Preferred stock, liquidation preference (in dollars per share)			$ 25	$ 25
Preferred stock, shares authorized (in shares)			50,000,000	50,000,000
Preferred stock, par value (in dollars per share)			$ 0.01	$ 0.01
Preferred stock, shares issued (in shares)			0	1,610,000
Accrued tax liability from REIT Testing				$ 1,960,000
Redeemable Preferred Stock
Debt and Equity Securities, FV-NI [Line Items]
Preferred stock, shares outstanding (in shares)	1,610,000
Preferred stock, dividend rate (percentage)	8.75%
Preferred stock, liquidation preference (in dollars per share)	$ 25
Collateralized Loan Obligations
Debt and Equity Securities, FV-NI [Line Items]
Maximum exposure to loss from consolidated trusts			$ 124,046,671	$ 124,046,671
Stock Repurchase Program
Debt and Equity Securities, FV-NI [Line Items]
Stock repurchase program, authorized amount					$ 10,000,000