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Mortgage Revenue Bonds - Schedule of MRB Redeemed (Details) - Redemption of Mortgage Revenue Bonds [Member]	9 Months Ended
	Sep. 30, 2025 USD ($) Unit	Sep. 30, 2024 USD ($) Unit
Schedule Of Available For Sale Securities [Line Items]
Principal Outstanding at Date of Redemption	$ 42,913,466	$ 21,615,000
Lutheran Gardens [Member] | Compton, CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed	March 2025
Units | Unit	76
Original Maturity Date	Feb. 01, 2025
Interest Rate	4.90%
Principal Outstanding at Date of Redemption	$ 10,352,000
Companion at Thornhill Apartments [Member] | Lexington, SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed	June 2025
Units | Unit	180
Original Maturity Date	Jan. 01, 2052
Interest Rate	5.80%
Principal Outstanding at Date of Redemption	$ 10,402,953
The Palms at Premier Park Apartments [Member] | Columbia, SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed	June 2025
Units | Unit	240
Original Maturity Date	Jan. 01, 2050
Interest Rate	6.25%
Principal Outstanding at Date of Redemption	$ 17,443,513
Copper Gate Apartments [Member] | Lafayette, IN [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed	August 2025
Units | Unit	129
Original Maturity Date	Dec. 01, 2029
Interest Rate	6.25%
Principal Outstanding at Date of Redemption	$ 4,715,000
Southpark [Member] | Austin,TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed		July 2024
Units | Unit		192
Original Maturity Date		Dec. 01, 2049
Interest Rate		6.13%
Principal Outstanding at Date of Redemption		$ 12,300,000
Runnymede [Member] | Austin,TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed		August 2024
Units | Unit		252
Original Maturity Date		Oct. 01, 2024
Interest Rate		6.00%
Principal Outstanding at Date of Redemption		$ 9,315,000

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-Number 210
-Section 12
-Subsection 29
-Paragraph Column C
-Publisher SEC

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