| **Accumulated Other Comprehensive Income (Tables)**                    | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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| **Equity [Abstract]**                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Changes in Accumulated Other Comprehensive Income (Loss)               | The 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, 2015 $(3,017) $(324) $(4,134) $(7,475)Other comprehensive income (loss) before reclassifications 1,043 (521) (65) 457Amounts reclassified from accumulated other comprehensive income — 5 — 5Net current period other comprehensive income  (loss) 1,043 (516) (65) 462Ending balance September 30, 2015 $(1,974) $(840) $(4,199) $(7,013)(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 (loss) before reclassifications 8,050 (18) — 8,032Amounts reclassified from accumulated other comprehensive income (466) — — (466)Net current period other comprehensive income (loss) 7,584 (18) — 7,566Ending balance September 30, 2014 $(6,892) $(18) $(3,129) $(10,039) |
| Reclassifications out of Accumulated Other Comprehensive Income (Loss) | The following table presents the reclassifications out of our accumulated other comprehensive income (loss) for the three and nine months ended September 30, 2015 and 2014:(Dollars in thousands)Amount Reclassified from AOCI   For Three Months Ended For Nine Months Ended   September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Line Item in the Consolidated Statement of OperationsAvailable-for-sale securities:         Net realized gains on sale of securities$— $(34) $— $(754) Securities gains, netIncome tax expense— 13 — 288 Income tax expenseTotal, net of tax— (21) — (466)            Interest rate swaps:         Swap ineffectiveness expense2 — 8 — Other expenseIncome tax benefit(1) — (3) — Income tax expenseTotal, net of tax1 — 5 —  Total reclassifications for the period$1 $(21) $5 $(466)                                                                                                                                                                                                                                                                                           |

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| - References
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| - Definition
Tabular disclosure of information about items reclassified out of accumulated other comprehensive income (loss).
+ References
No definition available.
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| - Definition
Tabular disclosure of the components of accumulated other comprehensive income (loss).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580
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