| **Other Comprehensive Income (Loss)** | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
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| **Equity [Abstract]**                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| Other Comprehensive Income (Loss)     | Other Comprehensive Income (Loss)The following table summarizes activity in the unrealized gain or loss on available for sale securities included in other comprehensive income (loss) for the three months ended March 31, 2015 and 2014. For the three months ended March 31,  20152014 Balance at beginning of period$2,522,000$(6,591,000) Unrealized gains arising during the period1,483,0007,457,000 Reclassification of realized gains during the period(1,395,000)(36,000) Related deferred taxes(31,000)(2,597,000) Net change57,0004,824,000 Balance at end of period$2,579,000$(1,767,000) The reclassification of realized gains is included in the net securities gains line of the consolidated statements of income and comprehensive income and the tax effect is included in the income tax expense line of the same statement.The following table summarizes activity in the unrealized loss on securities transferred from available for sale to held to maturity included in other comprehensive income (loss) for the three months ended March 31, 2015 and 2014. For the three months ended March 31, 20152014Balance at beginning of period$(48,000)$—Net unrealized losses transferred during the period——Amortization of net unrealized losses(14,000)—Related deferred taxes(5,000)—Net change(19,000)—Balance at end of period$(67,000)$—The following table summarizes activity in the unrealized gain or loss on postretirement benefits included in other comprehensive income (loss) for the three months ended March 31, 2015 and 2014. For the three months ended March 31, 20152014Unrecognized postretirement benefits at beginning of period$(125,000)$188,000Amortization of unrecognized transition obligation——Change in unamortized net actuarial gain (loss)——Related deferred taxes——Unrecognized postretirement benefits at end of period$(125,000)$188,000 |

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