| **Other Long-term Debt (Tables)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
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| **Debt Disclosure [Abstract]**    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Summary of Other Long-Term Debt   | Other long-term debt at December 31 follows: 2014 2013 Amount WeightedAverageContractualRate WeightedAverageEffectiveRate Amount WeightedAverageContractualRate WeightedAverageEffectiveRate (dollars in thousands)Borrowings from FHLB due:           2014      $57,892 1.13% 1.13%2015$80,142 0.82% 0.82% 79,971 0.82 0.822016563 3.82 3.82 389 4.64 4.642017585 3.83 3.83 407 4.64 4.642018607 3.83 3.83 426 4.64 4.642019631 3.84 3.84      Thereafter6,931 3.81 3.81 5,300 4.66 4.66Total$89,459     $144,385     |

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