| **Accumulated Other Comprehensive Income (Tables)**                                       | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| **Statement of Other Comprehensive Income [Abstract]**                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| Changes in Accumulated Other Comprehensive Income (Loss) [Table Text Block]               | The following table presents the changes in our accumulated other comprehensive income (loss), net of tax, by component for the period indicated:(Dollars in thousands) Unrealized Gains (Losses) on Available For Sale Securities Defined Benefit Plan Items Total       Beginning balance January 1, 2013 $3,650 $(3,973) $(323)Other comprehensive income (loss) before reclassifications (12,221) — (12,221)Amounts reclassified from accumulated other comprehensive income (1,679) (461) (2,140)Net current period other comprehensive income (13,900) (461) (14,361)Ending balance September 30, 2013 $(10,250) $(4,434) $(14,684)                                                                                                                                                                                                                                                                |
| Reclassifications out of Accumulated Other Comprehensive Income (Loss) [Table Text Block] | The following table presents the reclassifications out of our accumulated other comprehensive income (loss) for the three and nine months ended September 30, 2013:(Dollars in thousands)Amount Reclassified from AOCI   Three Months Ended September 30, 2013 Nine Months Ended September 30, 2013 Line Item in the Consolidated Statement of OperationsAvailable for sale securities:     Net realized gains on sale of securities$(50) $(2,773) Securities gains (losses), netIncome tax benefit (expense)19 1,095 Income tax benefit (expense)Total, net of tax(31) (1,678)        Defined benefit plan items:        Net actuarial gains(249) (762) Personnel expenseIncome tax benefit (expense)95 301 Income tax benefit (expense)Total, net of tax(154) (461)  Total reclassifications for the period$(185) $(2,139)   |

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