Investments and Fair Value - Valuation techniques and unobservable inputs (Details)	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Fair Value Measurement Inputs and Valuation Techniques
Fair Value	$ 113,050,141	$ 110,509,905
Obligations under participation agreements, at fair value (proceeds of $6,088,283 and $4,863,009, respectively)	6,114,979	4,883,877
Mortgage Loan
Fair Value Measurement Inputs and Valuation Techniques
Fair Value	76,311,192	61,281,259
Loans Held For Investment Acquired Through Participation
Fair Value Measurement Inputs and Valuation Techniques
Fair Value	36,738,949	48,349,374
Level 3
Fair Value Measurement Inputs and Valuation Techniques
Fair Value	113,050,141	109,630,633
Level 3 \| Obligations Under Participation Agreements
Fair Value Measurement Inputs and Valuation Techniques
Obligations under participation agreements, at fair value (proceeds of $6,088,283 and $4,863,009, respectively)	6,114,979	4,883,877
Level 3 \| Mortgage Loan
Fair Value Measurement Inputs and Valuation Techniques
Fair Value	76,311,192	61,281,259
Level 3 \| Loans Held For Investment Acquired Through Participation
Fair Value Measurement Inputs and Valuation Techniques
Fair Value	$ 36,738,949	$ 48,349,374
Level 3 \| Discounted Cash Flow \| Discount Rate \| Obligations Under Participation Agreements \| Minimum
Fair Value Measurement Inputs and Valuation Techniques
Discount rate	0.1114	0.0825
Level 3 \| Discounted Cash Flow \| Discount Rate \| Obligations Under Participation Agreements \| Maximum
Fair Value Measurement Inputs and Valuation Techniques
Discount rate	0.1114	0.0825
Level 3 \| Discounted Cash Flow \| Discount Rate \| Obligations Under Participation Agreements \| Weighted average
Fair Value Measurement Inputs and Valuation Techniques
Discount rate	0.1114	0.0825
Level 3 \| Discounted Cash Flow \| Discount Rate \| Mortgage Loan \| Minimum
Fair Value Measurement Inputs and Valuation Techniques
Discount rate	0.1114	0.0825
Level 3 \| Discounted Cash Flow \| Discount Rate \| Mortgage Loan \| Maximum
Fair Value Measurement Inputs and Valuation Techniques
Discount rate	0.1804	0.1500
Level 3 \| Discounted Cash Flow \| Discount Rate \| Mortgage Loan \| Weighted average
Fair Value Measurement Inputs and Valuation Techniques
Discount rate	0.1412	0.1258
Level 3 \| Discounted Cash Flow \| Discount Rate \| Loans Held For Investment Acquired Through Participation \| Minimum
Fair Value Measurement Inputs and Valuation Techniques
Discount rate	0.1500	0.1237
Level 3 \| Discounted Cash Flow \| Discount Rate \| Loans Held For Investment Acquired Through Participation \| Maximum
Fair Value Measurement Inputs and Valuation Techniques
Discount rate	0.1525	0.1500
Level 3 \| Discounted Cash Flow \| Discount Rate \| Loans Held For Investment Acquired Through Participation \| Weighted average
Fair Value Measurement Inputs and Valuation Techniques
Discount rate	0.1505	0.1440

Value of input used to measure alternative investment.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
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+ References

No definition available.

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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 5D
-Subparagraph (SX 210.12-13D(Column C))
-URI http://asc.fasb.org/extlink&oid=122147990&loc=SL120429264-123010

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-12B(Column C))
-URI http://asc.fasb.org/extlink&oid=122147990&loc=d3e611197-123010

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 30
-Section 50
-Paragraph 1
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