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Note 8 - Commitments and Off-balance Sheet Risk (Tables) | 9 Months Ended
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Sep. 30, 2023
Notes Tables |
Summary of Contractual Amounts of Financial Instruments With Off Balance Sheet Risk [Table Text Block] |
|  | September 30, |  |  | December 31, |
|  | 2023 |  |  | 2022 |
Commercial unused lines of credit |  | $ | 1,603,414,000 |  |  | $ | 1,283,703,000 |
Unused lines of credit secured by 1–4 family residential properties |  |  | 74,130,000 |  |  |  | 71,972,000 |
Credit card unused lines of credit |  |  | 135,886,000 |  |  |  | 123,687,000 |
Other consumer unused lines of credit |  |  | 58,486,000 |  |  |  | 75,747,000 |
Commitments to make loans |  |  | 287,510,000 |  |  |  | 329,646,000 |
Standby letters of credit |  |  | 19,367,000 |  |  |  | 23,539,000 |
|  | $ | 2,178,793,000 |  |  | $ | 1,908,294,000 |

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