| **Accumulated Other Comprehensive Income (Notes)**     | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
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| **Statement of Other Comprehensive Income [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| Accumulated Other Comprehensive Income                 | Accumulated Other Comprehensive IncomeThe 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 before reclassifications (12,976) — (12,976)   Amounts reclassified from accumulated other comprehensive income (1,647) (308) (1,955)Net current period other comprehensive income (14,623) (308) (14,931)Ending balance June 30, 2013 $(10,973) $(4,281) $(15,254)The following table presents the reclassifications out of our accumulated other comprehensive income (loss) for the three and six months ended June 30, 2013:(Dollars in thousands)Amount Reclassified from AOCI   Three Months Ended June 30, 2013 Six Months Ended June 30, 2013 Line Item in the Statement Where Net Income is PresentedAvailable for sale securities:      $(346) $(2,723) Net realized gains on sale of securities 137 1,076 Income tax benefit (expense) (209) (1,647) Total, net of taxDefined benefit plan items:        Net actuarial gains(255) (509) Personnel expense 101 201 Income tax benefit (expense) (154) (308) Total, net of taxTotal reclassifications for the period$(363) $(1,955) Total, net of tax |

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Accumulated Other Comprehensive Income (Loss) [Text Block]
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