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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
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Schedule of Available-for-sale Securities [Line Items] |  |  |
Assets at Fair Value, beginning balance |  | $ 952,333,636 | $ 816,370,069
Total gains (losses) (realized/unrealized) [Abstract] |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | $ 65,102 | $ 1,388,828
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
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
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
Total gain (losses) included in other comprehensive (loss) income |  | $ (12,071,696) | $ 20,510,089
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances |  | 27,297,798 | 62,427,813
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions |  | (13,763,624) | (14,670,016)
Assets at Fair Value, ending balance |  | 953,861,216 | 886,026,783
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 |  | 16,924 | 10,943
Interest Rate Derivative Instruments [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Derivative Assets (Liabilities) at Fair Value, beginning balance |  | 265 | 331,240
Total gains (losses) (realized/unrealized) [Abstract] |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | (231) | 1,317,385
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements and redemptions |  |  | (1,363,480)
Derivative Assets (Liabilities) at Fair Value, ending balance |  | 34 | 285,145
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 |  | (231) | (6,024)
Bond Purchase Commitment [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Assets at Fair Value, beginning balance |  | 197,788 | 98,929
Total gains (losses) (realized/unrealized) [Abstract] |  |  |
Total gain (losses) included in other comprehensive (loss) income |  | (62,959) | 112,547
Assets at Fair Value, ending balance |  | 134,829 | 211,476
Taxable Mortgage Revenue Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Assets at Fair Value, beginning balance |  | 21,460,288 | 16,531,896
Total gains (losses) (realized/unrealized) [Abstract] |  |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | (6,050) | (6,050)
Total gain (losses) included in other comprehensive (loss) income |  | 29,577 | (181,509)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances |  | 1,000,000 | 1,805,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions |  | (11,503,059) | (2,797)
Assets at Fair Value, ending balance |  | 10,980,756 | 18,146,540
Mortgage Revenue Bonds [Member] |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Assets at Fair Value, beginning balance | [1] | 930,675,295 | 799,408,004
Total gains (losses) (realized/unrealized) [Abstract] |  |  |
Total gain (losses) included in earnings (interest income and interest expense) | [1] | 71,383 | 77,493
Total gain (losses) included in other comprehensive (loss) income | [1] | (12,038,314) | 20,579,051
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances | [1] | 26,297,798 | 60,622,813
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions | [1] | (2,260,565) | (13,303,739)
Assets at Fair Value, ending balance | [1] | 942,745,597 | 867,383,622
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] | $ 17,155 | $ 16,967
[1] | Mortgage revenue bonds includes both bonds held in trust as well as those held by the Partnership.

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