| **Accumulated Other Comprehensive Income** | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| **Equity [Abstract]**                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Accumulated Other Comprehensive Income     | Accumulated Other Comprehensive IncomeThe following tables present the changes in our accumulated other comprehensive income (loss), net of tax, by component for the periods indicated:(Dollars in thousands) Unrealized Gains (Losses) on Available-For-Sale Securities Interest Rate Swaps Defined Benefit Plan Items Total         Beginning balance January 1, 2014 $(14,476) $— $(3,129) $(17,605)Other comprehensive income before reclassifications 8,372 (230) — 8,142Amounts reclassified from accumulated other comprehensive income (445) — — (445)Net current period other comprehensive income 7,927 (230) — 7,697Ending balance June 30, 2014 $(6,549) $(230) $(3,129) $(9,908)(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 loss before reclassifications (12,976) — (12,976)Amounts reclassified from accumulated other comprehensive income (1,647) (308) (1,955)Net current period other comprehensive loss (14,623) (308) (14,931)Ending balance June 30, 2013 $(10,973) $(4,281) $(15,254)The following table presents the reclassifications out of our accumulated other comprehensive income (loss) for the three months and six months ended , June 30, 2014 and 2013:(Dollars in thousands)Amount Reclassified from AOCI   Three Months Ended June 30, 2014 Three Months Ended June 30, 2013 Six Months Ended June 30, 2014 Six Months Ended June 30, 2013 Line Item in the Consolidated Statement of OperationsAvailable-for-sale securities:         Net realized gains on sale of securities$(720) $(345) $(720) $(2,723) Securities gains, netIncome tax (benefit) expense275 136 275 1,076 Income tax expenseTotal, net of tax(445) (209) (445) (1,647)            Defined benefit plan items:            Net actuarial gains— (255) — (509) Personnel expenseIncome tax (benefit) expense— 101 — 201 Income tax expenseTotal, net of tax— (154) — (308)  Total reclassifications for the period$(445) $(363) $(445) $(1,955)   |

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Accumulated Other Comprehensive Income (Loss) [Text Block]
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