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Note 8 - Commitments and Off-Balance Sheet Risk (Tables) | 3 Months Ended
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Mar. 31, 2018
Notes Tables |
Summary of Contractual Amounts of Financial Instruments With Off Balance Sheet Risk [Table Text Block] |
|  | March 31, |  |  | December 31, |
|  | 2018 |  |  | 2017 |
Commercial unused lines of credit |  | $ | 678,832,000 |  |  | $ | 682,202,000 |
Unused lines of credit secured by 1 – 4 family residential properties |  |  | 60,930,000 |  |  |  | 61,606,000 |
Credit card unused lines of credit |  |  | 42,693,000 |  |  |  | 39,807,000 |
Other consumer unused lines of credit |  |  | 17,788,000 |  |  |  | 17,629,000 |
Commitments to make loans |  |  | 238,437,000 |  |  |  | 184,923,000 |
Standby letters of credit |  |  | 23,592,000 |  |  |  | 26,030,000 |
|  | $ | 1,062,272,000 |  |  | $ | 1,012,197,000 |

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