COMMERCIAL MORTGAGE LOANS HELD-FOR-INVESTMENT - Loan Portfolio Activity (Details) - USD ($)	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Commercial Mortgage Loans Held-for-Investment
Purchases and fundings	$ 269,596,827	$ 647,459,391
Principal payments	(247,335,751)	(391,394,015)
Accretion of purchase discount	125,098	24,773
Amortization of purchase premium	(55,804)	$ (361,227)
Commercial Real Estate Portfolio Segment
Commercial Mortgage Loans Held-for-Investment
Balance at December 31, 2021	1,001,825,294
Purchases and fundings	269,596,827
Principal payments	(225,537,724)
Accretion of purchase discount	125,098
Amortization of purchase premium	(55,804)
Provision for loan losses	(1,872,937)
Balance at September 30, 2022	$ 1,044,080,754

Accretion of Discounts on Held-for-investment Loans

No definition available.

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- Definition

Allowance For Loan Losses

+ References

No definition available.

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- Definition

Amortization of Premiums on Held-for-investment Loans

+ References

No definition available.

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- Definition

Loans Receivable Held-For-Investment, Net, Reconciliation To Cash Flow [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

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- Definition

The cash outflow associated with purchasing loans held for investment purposes during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3213-108585

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- Definition

The cash inflow from repayments of the balance excluding interest (principal) on loans receivable and leases held for investment purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3179-108585

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