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Note 8 - Commitments and Off-Balance Sheet Risk (Tables) | 3 Months Ended
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Mar. 31, 2019
Notes Tables |
Summary of Contractual Amounts of Financial Instruments With Off Balance Sheet Risk [Table Text Block] |
|  | March 31, |  |  | December 31, |
|  | 2019 |  |  | 2018 |
Commercial unused lines of credit |  | $ | 759,338,000 |  |  | $ | 784,895,000 |
Unused lines of credit secured by 1 – 4 family residential properties |  |  | 57,030,000 |  |  |  | 57,378,000 |
Credit card unused lines of credit |  |  | 51,305,000 |  |  |  | 47,432,000 |
Other consumer unused lines of credit |  |  | 20,253,000 |  |  |  | 20,231,000 |
Commitments to make loans |  |  | 126,590,000 |  |  |  | 101,517,000 |
Standby letters of credit |  |  | 23,154,000 |  |  |  | 25,322,000 |
|  | $ | 1,037,670,000 |  |  | $ | 1,036,775,000 |

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