COMMERCIAL MORTGAGE LOANS HELD-FOR-INVESTMENT - Summary of Commercial Loan Risk Ratings (Details)	9 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) mortgage_loan		Dec. 31, 2019 USD ($) mortgage_loan
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial mortgage loans held-for-investment, at amortized cost	$ 598,933,122	[1]	$ 635,260,420
Average risk rating, moderate	3.1		2.8
Commercial real estate portfolio segment
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans | mortgage_loan	44		51
Unpaid Principal Balance	$ 598,933,122		$ 635,260,420
Commercial mortgage loans held-for-investment, at amortized cost	$ 598,933,122		$ 635,260,420
Commercial real estate portfolio segment | Risk rating, 1
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans | mortgage_loan	0		1
Unpaid Principal Balance	$ 0		$ 9,000,000
Commercial mortgage loans held-for-investment, at amortized cost	$ 0		$ 9,000,000
Commercial real estate portfolio segment | Risk rating, 2
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans | mortgage_loan	8		9
Unpaid Principal Balance	$ 91,155,086		$ 87,176,088
Commercial mortgage loans held-for-investment, at amortized cost	$ 91,155,086		$ 87,176,088
Commercial real estate portfolio segment | Risk rating, 3
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans | mortgage_loan	27		37
Unpaid Principal Balance	$ 393,803,374		$ 487,513,256
Commercial mortgage loans held-for-investment, at amortized cost	$ 393,803,374		$ 487,513,256
Average risk rating, percentage	81.00%		91.90%
Commercial real estate portfolio segment | Risk rating, 4
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans | mortgage_loan	9		4
Unpaid Principal Balance	$ 113,974,662		$ 51,571,076
Commercial mortgage loans held-for-investment, at amortized cost	$ 113,974,662		$ 51,571,076
Commercial real estate portfolio segment | Risk rating, 5
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans | mortgage_loan	0		0
Unpaid Principal Balance	$ 0		$ 0
Commercial mortgage loans held-for-investment, at amortized cost	$ 0		$ 0

[1] Our consolidated balance sheets include assets and liabilities of consolidated variable interest entities ("VIEs") as the Company was the primary beneficiary of these VIEs. As of September 30, 2020 and December 31, 2019, assets of consolidated VIEs related to Hunt CRE 2017-F1, Ltd. and Hunt CRE 2018-FL2, Ltd. totaled $608,690,756 and $636,541,489, respectively and the liabilities of consolidated VIEs related to Hunt CRE 2017-FL1, Ltd. and Hunt CRE 2018-FL2, Ltd totaled $480,043,366 and $506,662,238 respectively. See Note 5 for further discussion.