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Note 9 - Commitments and Off-balance Sheet Risk (Tables) | 6 Months Ended
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Jun. 30, 2015
Disclosure Text Block Supplement [Abstract] |
Summary of Contractual Amounts of Financial Instruments with Off-balance Sheet Risk [Table Text Block] |
|  | June 30, |  |  | December 31, |
|  | 2015 |  |  | 2014 |
Commercial unused lines of credit |  | $ | 487,753,000 |  |  | $ | 554,856,000 |
Unused lines of credit secured by 1 – 4 family residential properties |  |  | 60,911,000 |  |  |  | 60,983,000 |
Credit card unused lines of credit |  |  | 12,911,000 |  |  |  | 11,649,000 |
Other consumer unused lines of credit |  |  | 7,321,000 |  |  |  | 8,673,000 |
Commitments to make loans |  |  | 243,013,000 |  |  |  | 110,126,000 |
Standby letters of credit |  |  | 34,774,000 |  |  |  | 35,461,000 |
|  | $ | 846,683,000 |  |  | $ | 781,748,000 |

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