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Fair Value of Financial Instruments - Summary of Activity Related to Level 3 Assets and Liabilities (Details) - Fair Value, Inputs, Level 3 [Member] - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |  |  |  |
Assets at Fair Value, beginning balance |  | $ 928,701,121 |  | $ 739,143,486 |  | $ 816,370,069 |  | $ 798,246,109 |
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |  |  |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | $ 1,285,386 |  | $ 2,952,972 |  | $ 4,057,755 |  | $ 6,359,920 |
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Interest Income (Expense), Net |  | Interest Income (Expense), Net |  | Interest Income (Expense), Net |  | Interest Income (Expense), Net |
Fair Value, Net Derivative Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Interest Income (Expense), Net |  | Interest Income (Expense), Net |  | Interest Income (Expense), Net |  | Interest Income (Expense), Net |
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] |  | OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax |  | OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax |  | OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax |  | OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax |
Total gain (losses) included in other comprehensive (loss) income |  | $ (48,024,749) |  | $ (22,780,560) |  | $ (39,087,606) |  | $ (91,367,669) |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances |  | 11,665,000 |  | 3,923,437 |  | 129,772,563 |  | 102,243,437 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions |  | (16,856,580) |  | (14,341,223) |  | (34,342,603) |  | (105,723,152) |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Other | [1] |  |  |  |  |  |  | (860,533) |
Assets at Fair Value, ending balance |  | 876,770,178 |  | 708,898,112 |  | 876,770,178 |  | 708,898,112 |
Total amount of gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets or liabilities held |  | (57,119) |  | 2,836 |  | (37,066) |  | 147,585 |
Interest Rate Derivative Instruments [Member] |  |  |  |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |  |  |  |
Derivative Assets (Liabilities) at Fair Value, beginning balance |  | 301,624 |  | 398,280 |  | 331,240 |  | 343,418 |
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |  |  |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  |  |  | 1,298,340 |  | 3,844,528 |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | 1,215,389 |  |  |  |  |  | 4,497,078 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions |  |  |  | (1,313,061) |  | (3,950,755) |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements and redemptions |  | (1,292,000) |  |  |  |  |  | (4,456,937) |
Derivative Assets (Liabilities) at Fair Value, ending balance |  | 225,013 |  | 383,559 |  | 225,013 |  | 383,559 |
Total amount of gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets or liabilities held |  | (74,463) |  | (14,509) |  | (88,722) |  | 107,617 |
Bond Purchase Commitment [Member] |  |  |  |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |  |  |  |
Assets at Fair Value, beginning balance |  | 138,100 |  | 8,953 |  | 98,929 |  | 964,404 |
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |  |  |  |  |
Total gain (losses) included in other comprehensive (loss) income |  | (250,548) |  | (91,864) |  | (211,377) |  | (1,047,315) |
Assets at Fair Value, ending balance |  | (112,448) |  | (82,911) |  | (112,448) |  | (82,911) |
Taxable Mortgage Revenue Bonds [Member] |  |  |  |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |  |  |  |
Assets at Fair Value, beginning balance |  | 22,297,418 |  | 11,457,256 |  | 16,531,896 |  | 3,428,443 |
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |  |  |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | (6,050) |  | (4,860) |  | (18,149) |  | (14,932) |
Total gain (losses) included in other comprehensive (loss) income |  | (1,676,780) |  | (221,686) |  | (2,213,376) |  | (553,379) |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances |  | 4,000,000 |  | 2,300,000 |  | 10,319,875 |  | 10,675,750 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions |  | (7,002,925) |  | (2,676) |  | (7,008,583) |  | (7,848) |
Assets at Fair Value, ending balance |  | 17,611,663 |  | 13,528,034 |  | 17,611,663 |  | 13,528,034 |
Mortgage Revenue Bonds [Member] |  |  |  |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |  |  |  |
Assets at Fair Value, beginning balance |  | 905,963,979 | [2] | 727,278,997 | [3] | 799,408,004 | [4] | 793,509,844 | [5]
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |  |  |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | 76,047 | [2] | 1,659,492 | [3] | 231,376 | [4] | 1,877,774 | [5]
Total gain (losses) included in other comprehensive (loss) income |  | (46,097,421) | [2] | (22,467,010) | [3] | (36,662,853) | [4] | (89,766,975) | [5]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances |  | 7,665,000 | [2] | 1,623,437 | [3] | 119,452,688 | [4] | 91,567,687 | [5]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions |  | (8,561,655) | [2] | (13,025,486) | [3] | (23,383,265) | [4] | (101,258,367) | [5]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Other | [1],[5] |  |  |  |  |  |  | (860,533) |
Assets at Fair Value, ending balance |  | 859,045,950 | [2],[4] | 695,069,430 | [3] | 859,045,950 | [2],[4] | 695,069,430 | [3]
Total amount of gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets or liabilities held |  | $ 17,344 | [2] | $ 17,345 | [3] | $ 51,656 | [4] | $ 39,968 | [5]
[1] | The other line is related to a re-allocation of the loan loss allowance upon restructuring of the Live 929 Apartments MRBs and property loan.
[2] | Mortgage revenue bonds includes both bonds held in trust as well as those held by the Partnership.
[3] | Mortgage revenue bonds includes both bonds held in trust as well as those held by the Partnership.
[4] | Mortgage revenue bonds includes both bonds held in trust as well as those held by the Partnership.
[5] | Mortgage revenue bonds includes both bonds held in trust as well as those held by the Partnership.

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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) recognized in income from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-3 + Details
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