| **Accumulated Other Comprehensive Income (Notes)**     | 3 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 the Company's 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 (2,985) — (2,985)   Amounts reclassified from accumulated other comprehensive income (1,438) (154) (1,592)Net current period other comprehensive income (4,423) (154) (4,577)Ending balance March 31, 2013 $(773) $(4,127) $(4,900)The following table presents the reclassifications out of the Company's accumulated other comprehensive income (loss) for the period indicated:(Dollars in thousands) Amount reclassified from AOCI Line item in the Statement where net income is presentedAvailable for sale securities:      $(2,377) Net realized gains on sale of securities  939 Income tax benefit (expense)  (1,438) Total, net of taxDefined benefit plan items:       Net actuarial gains (254) Personnel expense  100 Income tax benefit (expense)  (154) Total, net of taxTotal reclassifications for the period $(1,592) Total, net of tax |

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Accumulated Other Comprehensive Income (Loss) [Text Block]
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