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Note 3 - Loans and Allowance for Loan Losses - Concentrations Within the Loan Portfolio (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Financing Receivable, before Allowance for Credit Loss | $ 4,600,781 | $ 4,303,758
Commercial Real Estate Loans to Lessors of Non Residential Buildings [Member] |  |
Financing Receivable, before Allowance for Credit Loss | $ 822,402 | $ 754,611
Percent of portfolio | 17.90% | 17.50%

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