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Note 4 - Loans - Schedule of Financing Receivables (Details) - USD ($) | Sep. 30, 2025 | Jun. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | --- | --- | --- | --- | ---
Total loans | $ 671,771,935 |  | $ 714,337,185 |  |  |
Allowance for credit losses | (2,540,950) | $ (2,590,950) | (2,620,949) | $ (2,747,949) | $ (2,747,949) | $ (2,785,949)
Net loans | 669,230,985 |  | 711,716,236 |  |  |
Residential Portfolio Segment [Member] | Real Estate Loan [Member] |  |  |  |  |  |
Total loans | 449,596,294 |  | 472,747,542 |  |  |
Allowance for credit losses | (1,619,601) | (1,660,885) | (1,680,949) | (1,826,538) | (1,836,909) | (1,851,969)
Commercial and Multi-Family Real Estate [Member] | Real Estate Loan [Member] |  |  |  |  |  |
Total loans | 122,811,801 |  | 118,008,866 |  |  |
Multi-Family Real Estate [Member] | Real Estate Loan [Member] |  |  |  |  |  |
Total loans | 70,364,169 |  | 74,152,418 |  |  |
Allowance for credit losses | (288,041) | (278,916) | (289,000) | (313,221) | (315,495) | (317,300)
Construction Loans [Member] | Real Estate Loan [Member] |  |  |  |  |  |
Total loans | 25,231,859 |  | 43,183,657 |  |  |
Allowance for credit losses | (58,786) | (92,712) | (123,000) | (112,118) | (105,426) | (157,500)
Commercial and Industrial [Member] |  |  |  |  |  |
Total loans | 3,703,476 |  | 6,163,747 |  |  |
Allowance for credit losses | (17,777) | (24,340) | (20,000) | (33,757) | (33,221) | (22,000)
Commercial and Industrial [Member] | Real Estate Loan [Member] |  |  |  |  |  |
Total loans | 3,703,476 |  | 6,163,747 |  |  |
Consumer Portfolio Segment [Member] |  |  |  |  |  |
Total loans | 64,336 |  | 80,955 |  |  |
Allowance for credit losses | (187) | $ (223) | 0 | $ 0 | $ 0 | $ 0
Consumer Portfolio Segment [Member] | Consumer Loans [Member] |  |  |  |  |  |
Total loans | $ 64,336 |  | $ 80,955 |  |  |

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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
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