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Note 5 - Allowance for Credit Losses on Loans and Nonperforming Assets - Financing Receivable, Troubled Debt Restructurings (Details) - Commercial Real Estate Portfolio Segment [Member] - Commercial Real Estate, Owner Occupied [Member] - Interest Only Payments [Member] - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
amortized cost | $ 6,396 | $ 6,396
Percentage | 4.48% | 5.46%
Commercial real estate owner-occupied (Month) | 3 months | 6 months

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