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Note 5 - Allowance for Credit Losses on Loans and Nonperforming Assets (Details Textual) | 12 Months Ended
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Dec. 31, 2025 USD ($) Securities | Dec. 31, 2024 Securities
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Maximum Loan amount indicated as risk graded | $ 400,000 |
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | Securities | 0 | 0
Commercial Real Estate, Owner Occupied [Member] | Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member] | Valuation Technique, Fair Value of Collateral Method [Member] |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment | $ 0 |

X
- Definition Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment. + References No definition available. + Details
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- Definition Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default. + References No definition available. + Details
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