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Note 4 - Loans, Allowance for Credit Losses and Other Real Estate Owned (Details Textual) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Nonaccrual | $ 2,347 |  | $ 2,347 |  | $ 201
Financing Receivable, Modified, Commitment to Lend | 0 |  | 0 |  | 0
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | 0 | $ 0 | 0 | $ 0 |
Financing Receivable, Held-for-Sale | 0 |  | 0 |  | 0
Other Real Estate | 0 |  | 0 |  | 0
Mortgage Loans in Process of Foreclosure, Amount | 0 |  | 0 |  | 0
Nonperforming Financial Instruments [Member] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Nonaccrual, Allowance | $ 700,000 |  | $ 700,000 |  |
Financing Receivable, Nonaccrual, Number of Loans | 1 |  | 1 |  |
Nonaccrual | $ 700,000 |  | $ 700,000 |  |
Commercial Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss and Revolving Loans, Writeoff | $ 1,559 |  | $ 1,559 |  | 0
Financing Receivable, Nonaccrual, Number of Loans | 1 |  | 1 |  |
Nonaccrual | $ 1,429 |  | $ 1,429 |  | 10
Collateral-dependent Loans, Balance | 199 |  | 199 |  |
Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss and Revolving Loans, Writeoff | 0 |  | 0 |  | 0
Nonaccrual | $ 918 |  | $ 918 |  | $ 191
Number of Collateral-dependent Loans | 6 |  | 6 |  | 9
Collateral-dependent Loans, Balance | $ 8,000 |  | $ 8,000 |  | $ 17,600
Consumer Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss and Revolving Loans, Writeoff | 68 |  | 595 |  | 388
Nonaccrual | 0 |  | 0 |  | 0
Collateral-dependent Loans, Balance | $ 246 |  | $ 246 |  | $ 503

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- Definition Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
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- Definition Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 16 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-16 + Details
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- Definition Amount, excluding accrued interest, of writeoff of financing receivable originated four years before current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 + Details
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