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Note 8 - Commitments and Off-balance Sheet Risk (Details Textual) - USD ($) | Mar. 31, 2022 | Dec. 31, 2021 | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss, Ending Balance | $ 35,153,000 | $ 35,363,000 | $ 38,695,000 | $ 37,967,000
Retail Lines of Credit and Credit Card Receivables [Member] | Maximum [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | $ 100,000 |  |  |

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