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Note 8 - Commitments and Off-balance Sheet Risk (Tables) | 3 Months Ended
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Mar. 31, 2022
Notes Tables |
Summary of Contractual Amounts of Financial Instruments With Off Balance Sheet Risk [Table Text Block] |
|  | March 31, |  |  | December 31, |
|  | 2022 |  |  | 2021 |
Commercial unused lines of credit |  | $ | 1,115,888,000 |  |  | $ | 1,098,951,000 |
Unused lines of credit secured by 1–4 family residential properties |  |  | 65,112,000 |  |  |  | 64,313,000 |
Credit card unused lines of credit |  |  | 95,813,000 |  |  |  | 92,146,000 |
Other consumer unused lines of credit |  |  | 72,544,000 |  |  |  | 64,876,000 |
Commitments to make loans |  |  | 158,102,000 |  |  |  | 212,476,000 |
Standby letters of credit |  |  | 32,954,000 |  |  |  | 33,109,000 |
|  | $ | 1,540,413,000 |  |  | $ | 1,565,871,000 |

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