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Note 4 - Loans - Schedule of Financing Receivables by Collateral (Details) - USD ($) | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Total loans | $ 671,771,935 | $ 714,337,185
Real Estate [Member] |  |
Total loans | 20,457,619 | 13,962,695
Other Collateral [Member] |  |
Total loans | 0 | 0
Commercial and Industrial [Member] |  |
Total loans | 3,703,476 | 6,163,747
Commercial and Industrial [Member] | Other Collateral [Member] |  |
Total loans | 0 | 0
Consumer Portfolio Segment [Member] |  |
Total loans | 64,336 | 80,955
Real Estate Loan [Member] | Residential Portfolio Segment [Member] |  |
Total loans | 449,596,294 | 472,747,542
Real Estate Loan [Member] | Residential Portfolio Segment [Member] | Real Estate [Member] |  |
Total loans | 2,502,938 | 1,863,957
Real Estate Loan [Member] | Residential Portfolio Segment [Member] | Other Collateral [Member] |  |
Total loans | 0 | 0
Real Estate Loan [Member] | Commercial Real Estate Portfolio Segment [Member] |  |
Total loans | 122,811,801 | 118,008,866
Real Estate Loan [Member] | Commercial Real Estate Portfolio Segment [Member] | Real Estate [Member] |  |
Total loans | 7,060,968 | 1,205,025
Real Estate Loan [Member] | Commercial Real Estate Portfolio Segment [Member] | Other Collateral [Member] |  |
Total loans | 0 | 0
Real Estate Loan [Member] | Multi-Family Real Estate [Member] |  |
Total loans | 70,364,169 | 74,152,418
Real Estate Loan [Member] | Multi-Family Real Estate [Member] | Other Collateral [Member] |  |
Total loans | 0 | 0
Real Estate Loan [Member] | Construction Loans [Member] |  |
Total loans | 25,231,859 | 43,183,657
Real Estate Loan [Member] | Construction Loans [Member] | Real Estate [Member] |  |
Total loans | 10,893,713 | 10,893,713
Real Estate Loan [Member] | Construction Loans [Member] | Other Collateral [Member] |  |
Total loans | 0 | 0
Real Estate Loan [Member] | Commercial and Industrial [Member] |  |
Total loans | 3,703,476 | 6,163,747
Consumer Loans [Member] | Consumer Portfolio Segment [Member] |  |
Total loans | 64,336 | 80,955
Consumer Loans [Member] | Consumer Portfolio Segment [Member] | Other Collateral [Member] |  |
Total loans | $ 0 | $ 0

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- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of 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 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-5 + Details
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