Mortgage Revenue Bonds - Schedule of MRBs Redeemed (Details)	6 Months Ended
Jun. 30, 2026 USD ($) Unit	Jun. 30, 2025 USD ($) Unit
Schedule Of Available For Sale Securities [Line Items]
Principal Outstanding at Date of Redemption	$ 43,879,465
Windsor Shores Apartments [Member] \| Columbia, SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Units \| Unit	176
Redemption of Mortgage Revenue Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Principal Outstanding at Date of Redemption	$ 117,130,000	$ 38,198,466
Redemption of Mortgage Revenue Bonds [Member] \| The Park at Sondrio [Member] \| Greenville, SC [Member] \| Series 2022A [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed	January 2026
Units \| Unit	271
Original Maturity Date	Jan. 01, 2030
Interest Rate	6.50%
Principal Outstanding at Date of Redemption	$ 38,100,000
Redemption of Mortgage Revenue Bonds [Member] \| The Park at Vietti [Member] \| Spartanburg, SC [Member] \| Series 2022A [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed	January 2026
Units \| Unit	204
Original Maturity Date	Jan. 01, 2030
Interest Rate	6.50%
Principal Outstanding at Date of Redemption	$ 26,985,000
Redemption of Mortgage Revenue Bonds [Member] \| Windsor Shores Apartments [Member] \| Columbia, SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed	February 2026
Units \| Unit	176
Original Maturity Date	Feb. 01, 2030
Interest Rate	6.50%
Principal Outstanding at Date of Redemption	$ 21,545,000
Redemption of Mortgage Revenue Bonds [Member] \| The Ivy Apartments (a/k/a Century Plaza Apartments) [Member] \| Greenville, SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Month Redeemed	February 2026
Units \| Unit	212
Original Maturity Date	Feb. 01, 2030
Interest Rate	6.50%
Principal Outstanding at Date of Redemption	$ 30,500,000
Redemption of Mortgage Revenue Bonds [Member] \| 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
Redemption of Mortgage Revenue Bonds [Member] \| 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
Redemption of Mortgage Revenue Bonds [Member] \| 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

Investment owned, redemption month.

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- Definition

Mortgage loans on real estate, redemption, face amount.

+ References

No definition available.

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- Definition

Maturity date of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, in YYYY-MM-DD format.

+ References

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Interest rate of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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- Definition

The number of units in a real estate property owned as of the balance sheet date.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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