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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
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Mar. 31, 2025 | Mar. 31, 2024
Schedule of Available-for-sale Securities [Line Items] |  |
Assets at Fair Value, beginning balance | $ 1,053,154,881 | $ 952,333,636
Total gains (losses) (realized/unrealized) [Abstract] |  |
Total gain (losses) included in earnings (interest income and interest expense) | $ 18,747 | $ 65,102
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
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
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 | $ (5,635,059) | $ (12,071,696)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances | 21,501,043 | 27,297,798
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions | (12,059,484) | (13,763,624)
Assets at Fair Value, ending balance | 1,056,980,128 | 953,861,216
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 | 16,967 | 16,924
Interest Rate Derivative Instruments [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Derivative Assets (Liabilities) at Fair Value, beginning balance |  | 265
Total gains (losses) (realized/unrealized) [Abstract] |  |
Total gain (losses) included in earnings (interest income and interest expense) |  | (231)
Derivative Assets (Liabilities) at Fair Value, ending balance |  | 34
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)
Bond Purchase Commitment [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Assets at Fair Value, beginning balance |  | 197,788
Total gains (losses) (realized/unrealized) [Abstract] |  |
Total gain (losses) included in other comprehensive (loss) income |  | (62,959)
Assets at Fair Value, ending balance |  | 134,829
Taxable Mortgage Revenue Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Assets at Fair Value, beginning balance | 26,671,085 | 21,460,288
Total gains (losses) (realized/unrealized) [Abstract] |  |
Total gain (losses) included in earnings (interest income and interest expense) | (3,312) | (6,050)
Total gain (losses) included in other comprehensive (loss) income | 486,738 | 29,577
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances | 7,400,000 | 1,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions | (138,347) | (11,503,059)
Assets at Fair Value, ending balance | 34,416,164 | 10,980,756
Mortgage Revenue Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Assets at Fair Value, beginning balance | 1,026,483,796 | 930,675,295
Total gains (losses) (realized/unrealized) [Abstract] |  |
Total gain (losses) included in earnings (interest income and interest expense) | 22,059 | 71,383
Total gain (losses) included in other comprehensive (loss) income | (6,121,797) | (12,038,314)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and advances | 14,101,043 | 26,297,798
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements and redemptions | (11,921,137) | (2,260,565)
Assets at Fair Value, ending balance | 1,022,563,964 | 942,745,597
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 | $ 16,967 | $ 17,155

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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 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 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2) -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 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 2: 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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