| **Investment Securities**                              | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                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| **Investments, Debt and Equity Securities [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              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| Investment Securities                                  | INVESTMENT SECURITIES The amortized cost, gross unrealized gains, gross unrealized losses and approximate fair value of the investment securities at the dates indicated were:  AmortizedCostGross Unrealized GainsGross Unrealized LossesFairValueAvailable for sale at March 31, 2015    U.S. Government-sponsored agency securities$100$7$107State and municipal249,69912,195$310261,584U.S. Government-sponsored mortgage-backed securities265,7408,94962274,627Corporate obligations3131Equity securities1,7061,706Total available for sale517,27621,151372538,055Held to maturity at March 31, 2015    State and municipal225,2256,42976231,578U.S. Government-sponsored mortgage-backed securities426,19312,988148439,033Total held to maturity651,41819,417224670,611Total Investment Securities$1,168,694$40,568$596$1,208,666  AmortizedCostGross Unrealized GainsGross Unrealized LossesFairValueAvailable for sale at December 31, 2014    U.S. Government-sponsored agency securities$100$9$109State and municipal216,91511,801$123228,593U.S. Government-sponsored mortgage-backed securities310,4608,771127319,104Corporate obligations3131Equity securities1,706  1,706Total available for sale529,21220,581250549,543Held to maturity at December 31, 2014    State and municipal204,4435,71696210,063U.S. Government-sponsored mortgage-backed securities426,64511,527512437,660Total held to maturity631,08817,243608647,723Total Investment Securities$1,160,300$37,824$858$1,197,266The amortized cost and fair value of available for sale securities and held to maturity securities at March 31, 2015, by contractual maturity, are shown below.  Expected maturities will differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Available for SaleHeld to Maturity AmortizedCostFairValueAmortizedCostFairValueMaturity Distribution at March 31, 2015:    Due in one year or less$3,836$3,869$8,072$8,121Due after one through five years8,9809,24519,56120,155Due after five through ten years50,22052,85386,27188,851Due after ten years186,794195,755111,321114,451 $249,830$261,722$225,225$231,578U.S. Government-sponsored mortgage-backed securities265,740274,627426,193439,033Equity securities1,7061,706Total Investment Securities$517,276$538,055$651,418$670,611The carrying value of securities pledged as collateral, to secure public deposits and for other purposes, was $458,131,000 at March 31, 2015, and $449,408,000 at December 31, 2014.The book value of securities sold under agreements to repurchase amounted to $129,110,000 at March 31, 2015, and $120,027,000 at December 31, 2014.Gross gains on the sales and redemptions of available for sale securities for the three months ended March 31, 2015, and 2014 are shown below.  There were no losses on the sale and redemption of available for sale securities, or other-than-temporary impairment losses recognized during the three months ended March 31, 2015, and 2014. Three Months EndedMarch 31,20152014Sales and Redemptions of Available for Sale Securities:  Gross gains$1,025$581  The following table shows investments securities with unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at March 31, 2015, and December 31, 2014:  Less than12 Months12 Months or LongerTotal FairValueGrossUnrealizedLossesFairValueGrossUnrealizedLossesFairValueGrossUnrealizedLossesTemporarily Impaired Available for Sale Securities at March 31, 2015      State and municipal$23,922$310$23,922$310U.S. Government-sponsored mortgage-backed securities4,87642,374587,25062Total Temporarily Impaired Available for Sale Securities28,7983142,3745831,172372Temporarily Impaired Held to Maturity Securities at March 31, 2015      State and municipal7,243767,24376U.S. Government-sponsored mortgage-backed securities4,9634211,62610616,589148Total Temporarily Impaired Held to Maturity Securities12,20611811,62610623,832224Total Temporarily Impaired Investment Securities$41,004$432$14,000$164$55,004$596  Less than12 Months12 Months or LongerTotal FairValueGrossUnrealizedLossesFairValueGrossUnrealizedLossesFairValueGrossUnrealizedLossesTemporarily Impaired Available for Sale Securities at December 31, 2014      State and municipal1,2567$9,850$116$11,106$123U.S. Government-sponsored mortgage-backed securities2,186135,4471147,633127Total Temporarily Impaired Available for Sale Securities3,4422015,29723018,739250Temporarily Impaired Held to Maturity Securities at December 31, 2014      State and municipal5,119962505,36996U.S. Government-sponsored mortgage-backed securities9,7918238,49143048,282512Total Temporarily Impaired Held to Maturity Securities14,91017838,74143053,651608Total Temporarily Impaired Investment Securities$18,352$198$54,038$660$72,390$858Certain investments in debt and equity securities are reported in the financial statements at an amount less than their historical cost as indicated in the table below.March 31, 2015December 31, 2014Investments reported at less than historical cost:  Historical cost$55,599$73,249Fair value$55,004$72,390Percent of the Corporation's available for sale and held to maturity portfolio4.6%6.1%Management believes the decline in fair value for these securities was temporary.  Should the impairment of any of these securities become other-than-temporary, the cost basis of the investment will be reduced and the resulting loss recognized in net income during the period the other-than-temporary ("OTTI") is identified.The Corporation’s management has evaluated all securities with unrealized losses for OTTI as of March 31, 2015.  The evaluations are based on the nature of the securities, the extent and duration of the loss and the intent and ability of the Corporation to hold these securities either to maturity or through the expected recovery period.In determining the fair value of the investment securities portfolio, the Corporation utilizes a third party for portfolio accounting services, including market value input, for those securities classified as Level 1 and Level 2 in the fair value hierarchy.  The Corporation has obtained an understanding of what inputs are being used by the vendor in pricing the portfolio and how the vendor was classifying these securities based upon these inputs.  From these discussions, the Corporation’s management is comfortable that the classifications are proper.  The Corporation has gained trust in the data for two reasons:  (a) independent spot testing of the data is conducted by the Corporation through obtaining market quotes from various brokers on a periodic basis and (b) actual gains or loss resulting from the sale of certain securities has proven the data to be accurate over time.  Fair value of securities classified as Level 3 in the valuation hierarchy was determined using a discounted cash flow model that incorporated market estimates of interest rates and volatility in markets that have not been active.State and MunicipalThe unrealized losses on the Corporation’s investments in securities of state and political subdivisions were caused by changes in interest rates.  The contractual terms of those investments do not permit the issuer to settle the securities at a price less than the amortized cost basis of the investments.  The Corporation does not intend to sell the investment and it is not more likely than not that the Corporation will be required to sell the investment before recovery of its new, lower amortized cost basis, which may be maturity.  The Corporation does not consider the investment securities to be other-than-temporarily impaired at March 31, 2015.U.S. Government-Sponsored Mortgage-Backed SecuritiesThe unrealized losses on the Corporation’s investment in U.S. Government-sponsored mortgage-backed securities were a result of changes in interest rates.  The Corporation expects to recover the amortized cost basis over the term of the securities as the decline in market value is attributable to changes in interest rates and not credit quality.  The Corporation does not intend to sell the investment and it is not more likely than not that the Corporation will be required to sell the investment before recovery of its new, lower amortized cost basis, which may be maturity.  The Corporation does not consider the investment securities to be other-than-temporarily impaired at March 31, 2015.Corporate ObligationsIn the first quarter of 2015, the Corporation sold its remaining trust preferred security which had no remaining book value as a result of OTTI of approximately $500,000 taken in 2009.   The sale of this security resulted in a gain of $45,000, which is included in the Consolidated Condensed Statement of Income in the current period.Credit Losses Recognized on InvestmentsCertain corporate obligations experienced fair value deterioration due to credit losses and other market factors.  The following table provides information about those securities for which only a credit loss was recognized in income and other losses were recorded in other comprehensive income.  AccumulatedCredit Losses in2015AccumulatedCredit Losses in2014Credit losses on debt securities held:  Balance, January 1$500$11,355Reductions for previous other-than-temporary losses realized on securities sold during the year(500)(10,855)Balance, March 31$—$500 |

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| - Definition
The entire disclosure for  investments in certain debt and equity securities.
+ References
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