| **Accumulated Other Comprehensive Income** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| **Equity [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 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 12,060 (331) (1,241) 10,488Amounts reclassified from accumulated other comprehensive income (601) 7 236 (358)Net current period other comprehensive income (loss) 11,459 (324) (1,005) 10,130Ending balance December 31, 2014 $(3,017) $(324) $(4,134) $(7,475)(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 (16,447) 1,031 (15,416)Amounts reclassified from accumulated other comprehensive income (1,679) (187) (1,866)Net current period other comprehensive income (loss) (18,126) 844 (17,282)Ending balance December 31, 2013 $(14,476) $(3,129) $(17,605)The following table shows the reclassifications out of accumulated other comprehensive income (loss) for the years ended December 31:(Dollars in thousands)Amount Reclassified from AOCI   2014 2013 Line Item in the Consolidated Statement of OperationsAvailable-for-sale securities:     Net realized gains on sale of securities$(974) $(2,772) Securities gains, netIncome tax expense373 1,093 Income tax expenseTotal, net of tax(601) (1,679)        Interest rate swaps:     Swap ineffectiveness expense12 — Miscellaneous expenseIncome tax benefit(5) — Income tax expenseTotal, net of tax7 —        Defined benefit plan items:     Net actuarial (gains) losses382 (302) Personnel expenseIncome tax (benefit) expense(146) 115 Income tax expenseTotal, net of tax236 (187)  Total reclassifications for the period$(358) $(1,866)   |

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| - Definition
The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e637-108580Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e681-108580Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e689-108580Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669619-108580Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e640-108580Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e716-108580Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e709-108580Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Reclassification Adjustments -URI http://asc.fasb.org/extlink&oid=6522872
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