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Note 8 - Commitments and Off-balance Sheet Risk (Tables) | 3 Months Ended
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Mar. 31, 2021
Notes Tables |
Summary of Contractual Amounts of Financial Instruments With Off Balance Sheet Risk [Table Text Block] |
|  | March 31, |  |  | December 31, |
|  | 2021 |  |  | 2020 |
Commercial unused lines of credit |  | $ | 1,052,778,000 |  |  | $ | 1,019,496,000 |
Unused lines of credit secured by 1 – 4 family residential properties |  |  | 59,986,000 |  |  |  | 59,396,000 |
Credit card unused lines of credit |  |  | 76,556,000 |  |  |  | 72,495,000 |
Other consumer unused lines of credit |  |  | 35,207,000 |  |  |  | 30,707,000 |
Commitments to make loans |  |  | 176,548,000 |  |  |  | 227,558,000 |
Standby letters of credit |  |  | 25,933,000 |  |  |  | 20,543,000 |
|  | $ | 1,427,008,000 |  |  | $ | 1,430,195,000 |

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