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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, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Assets at Fair Value, beginning balance |  | $ 1,018,024,584 | $ 928,701,121 | $ 952,333,636 | $ 816,370,069
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | $ 1,157,988 | $ 1,285,386 | 1,276,619 | $ 4,057,755
Total gain (losses) Included in earnings (impairment of securities and provision for credit loss) |  |  |  | 169,308 |
Total gain (losses) Included in earnings (gain on sale of securities) |  |  |  | $ 1,012,581 |
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Interest Income (Expense), Operating | Interest Income (Expense), Operating | Interest Income (Expense), Operating | Interest Income (Expense), Operating
Fair Value, Net Derivative Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Interest Income (Expense), Operating | Interest Income (Expense), Operating | Interest Income (Expense), Operating | Interest Income (Expense), Operating
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 |  | $ 17,577,958 | $ (48,024,749) | $ (5,190,307) | $ (39,087,606)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances |  | 40,512,542 | 11,665,000 | 151,262,402 | 129,772,563
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales |  |  |  | (8,221,234) |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions |  | (24,523,416) | (16,856,580) | (39,893,349) | (34,342,603)
Assets at Fair Value, ending balance |  | 1,052,749,656 | 876,770,178 | 1,052,749,656 | 876,770,178
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 | (57,119) | 220,887 | (37,066)
Interest Rate Derivative Instruments [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Derivative Assets (Liabilities) at Fair Value, beginning balance |  |  | 301,624 | 265 | 331,240
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  |  | 1,215,389 | (265) | 3,844,528
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements and redemptions |  |  | (1,292,000) |  | (3,950,755)
Derivative Assets (Liabilities) at Fair Value, ending balance |  | 0 | 225,013 | 0 | 225,013
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) | (265) | (88,722)
Bond Purchase Commitment [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Assets at Fair Value, beginning balance |  | 46,238 | 138,100 | 197,788 | 98,929
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |
Total gain (losses) included in other comprehensive (loss) income |  | (46,238) | (250,548) | (197,788) | (211,377)
Assets at Fair Value, ending balance |  | 0 | (112,448) | 0 | (112,448)
Taxable Mortgage Revenue Bonds [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Assets at Fair Value, beginning balance |  | 15,926,321 | 22,297,418 | 21,460,288 | 16,531,896
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | (3,073) | (6,050) | (12,017) | (18,149)
Total gain (losses) included in other comprehensive (loss) income |  | 938,468 | (1,676,780) | 842,634 | (2,213,376)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances |  | 4,000,000 | 4,000,000 | 10,077,000 | 10,319,875
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions |  | (1,003,200) | (7,002,925) | (12,509,389) | (7,008,583)
Assets at Fair Value, ending balance |  | 19,858,516 | 17,611,663 | 19,858,516 | 17,611,663
Mortgage Revenue Bonds [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Assets at Fair Value, beginning balance | [1] | 1,002,052,025 | 905,963,979 | 930,675,295 | 799,408,004
Total gains (losses) (realized/unrealized) [Abstract] |  |  |  |  |
Total gain (losses) included in earnings (interest income and interest expense) | [1] | 1,161,061 | 76,047 | 1,288,901 | 231,376
Total gain (losses) Included in earnings (impairment of securities and provision for credit loss) | [1] |  |  | 169,308 |
Total gain (losses) Included in earnings (gain on sale of securities) | [1] |  |  | 1,012,581 |
Total gain (losses) included in other comprehensive (loss) income | [1] | 16,685,728 | (46,097,421) | (5,835,153) | (36,662,853)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances | [1] | 36,512,542 | 7,665,000 | 141,185,402 | 119,452,688
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales | [1] |  |  | (8,221,234) |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions | [1] | (23,520,216) | (8,561,655) | (27,383,960) | (23,383,265)
Assets at Fair Value, ending balance | [1] | 1,032,891,140 | 859,045,950 | 1,032,891,140 | 859,045,950
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 | [1] | $ 17,344 | $ 17,344 | $ 221,152 | $ 51,656
[1] | Mortgage revenue bonds includes both bonds held in trust as well as those held by the Partnership.

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