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Note 7 - Loans and Related Allowance for Credit Losses - Troubled Debt Restructurings (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Modified, Amortized cost | $ 2,224 | $ 13,482 | $ 5,325 | $ 13,482
Total Financing Receivables, Percentage | 0.10% | 0.90% | 0.30% | 0.90%
Payment Deferral [Member] |  |  |  |
Modified, Amortized cost | $ 2,224 | $ 0 | $ 2,281 | $ 0
Extended Maturity [Member] |  |  |  |
Modified, Amortized cost | 0 | 13,482 | 3,044 | 13,482
Payment Deferral and Extended Maturity [Member] |  |  |  |
Modified, Amortized cost | 0 | 0 | 0 | 0
Interest Rate Reduction and Term Past Due [Member] |  |  |  |
Modified, Amortized cost | 0 | 0 | 0 | 0
Interest Rate Reduction and Principal Forgiveness [Member] |  |  |  |
Modified, Amortized cost | 0 | 0 | 0 | 0
Commercial And Industrial [Member] |  |  |  |
Modified, Amortized cost |  |  | $ 889 |
Total Financing Receivables, Percentage |  |  | 0.10% |
Commercial And Industrial [Member] | Payment Deferral [Member] |  |  |  |
Modified, Amortized cost |  |  | $ 0 |
Commercial And Industrial [Member] | Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  |  | 889 |
Commercial And Industrial [Member] | Payment Deferral and Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Commercial And Industrial [Member] | Interest Rate Reduction and Term Past Due [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Commercial And Industrial [Member] | Interest Rate Reduction and Principal Forgiveness [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Home Equity Lines of Credit [Member] |  |  |  |
Modified, Amortized cost |  |  | $ 100 |
Total Financing Receivables, Percentage |  |  | 0.00% |
Home Equity Lines of Credit [Member] | Payment Deferral [Member] |  |  |  |
Modified, Amortized cost |  |  | $ 0 |
Home Equity Lines of Credit [Member] | Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  |  | 100 |
Home Equity Lines of Credit [Member] | Payment Deferral and Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Home Equity Lines of Credit [Member] | Interest Rate Reduction and Term Past Due [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Home Equity Lines of Credit [Member] | Interest Rate Reduction and Principal Forgiveness [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Construction and Other [Member] |  |  |  |
Modified, Amortized cost |  |  | $ 2,055 |
Total Financing Receivables, Percentage |  |  | 0.10% |
Construction and Other [Member] | Payment Deferral [Member] |  |  |  |
Modified, Amortized cost |  |  | $ 0 |
Construction and Other [Member] | Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  |  | 2,055 |
Construction and Other [Member] | Payment Deferral and Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Construction and Other [Member] | Interest Rate Reduction and Term Past Due [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Construction and Other [Member] | Interest Rate Reduction and Principal Forgiveness [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] |  |  |  |
Modified, Amortized cost | $ 2,224 |  | $ 2,224 |
Total Financing Receivables, Percentage | 0.10% |  | 0.10% |
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Payment Deferral [Member] |  |  |  |
Modified, Amortized cost | $ 2,224 |  | $ 2,224 |
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Extended Maturity [Member] |  |  |  |
Modified, Amortized cost | 0 |  | 0 |
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Payment Deferral and Extended Maturity [Member] |  |  |  |
Modified, Amortized cost | 0 |  | 0 |
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Interest Rate Reduction and Term Past Due [Member] |  |  |  |
Modified, Amortized cost | 0 |  | 0 |
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Interest Rate Reduction and Principal Forgiveness [Member] |  |  |  |
Modified, Amortized cost | $ 0 |  | 0 |
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |  |  |
Modified, Amortized cost |  | $ 13,482 |  | $ 13,482
Total Financing Receivables, Percentage |  | 0.90% |  | 0.90%
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Payment Deferral [Member] |  |  |  |
Modified, Amortized cost |  | $ 0 |  | $ 0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  | 13,482 |  | 13,482
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Payment Deferral and Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  | 0 |  | 0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Interest Rate Reduction and Term Past Due [Member] |  |  |  |
Modified, Amortized cost |  | 0 |  | 0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Interest Rate Reduction and Principal Forgiveness [Member] |  |  |  |
Modified, Amortized cost |  | $ 0 |  | $ 0
Residential Portfolio Segment [Member] |  |  |  |
Modified, Amortized cost |  |  | $ 57 |
Total Financing Receivables, Percentage |  |  | 0.00% |
Residential Portfolio Segment [Member] | Payment Deferral [Member] |  |  |  |
Modified, Amortized cost |  |  | $ 57 |
Residential Portfolio Segment [Member] | Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Residential Portfolio Segment [Member] | Payment Deferral and Extended Maturity [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Residential Portfolio Segment [Member] | Interest Rate Reduction and Term Past Due [Member] |  |  |  |
Modified, Amortized cost |  |  | 0 |
Residential Portfolio Segment [Member] | Interest Rate Reduction and Principal Forgiveness [Member] |  |  |  |
Modified, Amortized cost |  |  | $ 0 |

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