USE OF SPECIAL PURPOSE ENTITIES AND VARIABLE INTEREST ENTITIES - Condensed Consolidated Balance Sheets (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Variable Interest Entity [Line Items]
Cash, cash equivalents and restricted cash	$ 65,989,168	$ 59,213,812	$ 53,915,473	$ 45,622,602
Accrued interest receivable	2,611,659	2,430,790
Investment related receivable	0	33,042,234
Loans held for investment	585,770,803	555,172,891
Total assets	659,406,989	679,352,035
Accrued interest payable	1,017,648	1,231,649
Collateralized loan obligations	504,460,023	503,978,918
Total liabilities	550,136,102	529,148,697
Equity	109,171,387	150,103,838
Total liabilities and equity	659,406,989	679,352,035
Hunt CRE 2017-FL1, Ltd.
Variable Interest Entity [Line Items]
Cash, cash equivalents and restricted cash	52,348,987	51,330,950
Accrued interest receivable	2,591,990	2,398,905
Investment related receivable	0	32,666,128
Loans held for investment	581,878,684	550,555,503
Total assets	636,819,661	636,951,486
Accrued interest payable	936,589	867,794
Collateralized loan obligations	504,460,023	503,978,918
Total liabilities	505,396,612	504,846,712
Equity	131,423,050	132,104,774
Total liabilities and equity	$ 636,819,661	$ 636,951,486