| **Premises and Equipment**                   | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| **Property, Plant and Equipment [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Premises and Equipment                       | Premises and EquipmentPremises and equipment at December 31 is summarized as follows: (dollars in thousands) 2014 2013Land $14,058 $14,460Building and improvements 47,542 49,463Furniture and equipment 39,641 43,648Leasehold improvements 906 1,017Premises and equipment, gross 102,147 108,588Accumulated depreciation and amortization (55,365) (57,699)Premises and equipment, net $46,782 $50,889Depreciation and amortization expense totaled $3.9 million, $3.7 million, and $3.8 million for the years ended December 31, 2014, 2013 and 2012, respectively. |

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| - Definition
The entire disclosure for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, accounting policies and methodology, roll forwards, depreciation, depletion and amortization expense, including composite depreciation, accumulated depreciation, depletion and amortization expense, useful lives and method used, income statement disclosures, assets held for sale and public utility disclosures.
+ References
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