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Note 8 - Commitments and Off-balance Sheet Risk (Tables) | 3 Months Ended
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Mar. 31, 2016
Disclosure Text Block Supplement [Abstract] |
Summary of Contractual Amounts of Financial Instruments with Off-balance Sheet Risk [Table Text Block] |
|  | March 31, |  |  | December 31, |
|  | 2016 |  |  | 2015 |
Commercial unused lines of credit |  | $ | 501,735,000 |  |  | $ | 522,658,000 |
Unused lines of credit secured by 1 – 4 family residential properties |  |  | 62,364,000 |  |  |  | 61,905,000 |
Credit card unused lines of credit |  |  | 16,874,000 |  |  |  | 15,612,000 |
Other consumer unused lines of credit |  |  | 6,497,000 |  |  |  | 8,583,000 |
Commitments to make loans |  |  | 218,392,000 |  |  |  | 178,034,000 |
Standby letters of credit |  |  | 33,567,000 |  |  |  | 34,946,000 |
|  | $ | 839,429,000 |  |  | $ | 821,738,000 |

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