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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] $ in Thousands | 12 Months Ended
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Dec. 31, 2025 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items] |
amortized cost | $ 6,396
Percentage | 4.48%
Commercial real estate owner-occupied (Month) | 3 months

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