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Note 13 - Commitments and Off-balance-sheet Risk (Details Textual) - USD ($) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss, Ending Balance | $ 42,246,000 | $ 35,363,000 | $ 37,967,000 | $ 23,889,000
Term Debt, Secured by Real Estate Balloon Payment, Period (Year) | 5 years |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | $ 3,916,619,000 | $ 3,453,459,000 |  |
London Interbank Offered Rate (LIBOR) [Member] |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | $ 368,000,000 |  |  |
Maximum [Member] |  |  |  |
Amortization Period for Term Debt, Secured by Real Estate (Year) | 25 years |  |  |
Term Debt Secured, by Non-real Estate Collateral Maturity Period (Year) | 7 years |  |  |
Minimum [Member] |  |  |  |
Amortization Period for Term Debt, Secured by Real Estate (Year) | 10 years |  |  |
Term Debt Secured, by Non-real Estate Collateral Maturity Period (Year) | 3 years |  |  |
Retail and Commercial Lines of Credit and Credit Card Receivables [Member] | Maximum [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | $ 100,000 |  |  |
Commercial Line of Credit Facilities [Member] | Maximum [Member] |  |  |  |
Line of Credit Facility, Expiration Period (Month) | 24 months |  |  |
Commercial Line of Credit Facilities [Member] | Minimum [Member] |  |  |  |
Line of Credit Facility, Expiration Period (Month) | 12 months |  |  |

X
- Definition Amortization period for the payments related to a credit facility, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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