| **Share-Based Compensation** | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                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| Share-Based Compensation     | NOTE 7. Share-Based CompensationStockoptions and restricted stock awards ("RSAs") have been issued todirectors, officers and other management employees under theCorporation's 1999 Long-term Equity Incentive Plan and the 2009Long-term Equity Incentive Plan.  The stock options,which have a ten-year life, become 100 percent vested ranging fromthree months to two years and are fully exercisable when vested.Option exercise prices equal the Corporation's common stock closingprice on NASDAQ on the date of grant.  RSAs provide forthe issuance of shares of the Corporation's common stock at no costto the holder and generally vest after three years.  TheRSAs vest only if the employee is actively employed by theCorporation on the vesting date and, therefore, any unvested sharesare forfeited.  RSAs for employees retired from theCorporation are either immediately vested at retirement or continueto vest after retirement, depending on which plan the shares weregranted under. Deferred stock units ("DSUs") have been credited tonon-employee directors who have elected to defer payment ofcompensation under the Corporation's 2008 Equity Compensation Planfor Non-employee Directors.  DSUs credited are equal tothe restricted shares that the non-employee director would havereceived under the plan.  As of September 30, 2011, alloutstanding DSUs have been converted to RSA’s due to directorretirements.TheCorporation’s 2009 Employee Stock Purchase Plan(“ESPP”) provides eligible employees of the Corporationand its subsidiaries an opportunity to purchase shares of commonstock of the Corporation through quarterly offerings financed bypayroll deductions. The price of the stock to be paid by theemployees shall be equal to 85 percent of the average of theclosing price of the Corporation’s common stock on eachtrading day during the offering period. However, in no event shallsuch purchase price be less than the lesser of an amount equal to85 percent of the market price of the Corporation’s stock onthe offering date or an amount equal to 85 percent of the marketvalue on the date of purchase. Common stock purchases are madequarterly and are paid through advance payroll deductions up to acalendar year maximum of $25,000.Compensationexpense related to unvested share-based awards is recorded byrecognizing the unamortized grant date fair value of these awardsover the remaining service periods of those awards, with no changein historical reported fair values and earnings. Awards are valuedat fair value in accordance with provisions of share-basedcompensation guidance and are recognized on a straight-line basisover the service periods of each award. To complete the exercise ofvested stock options, RSA’s and ESPP options, the Corporationgenerally issues new shares from its authorized but unissued sharepool. Share-based compensation for the three months and nine monthsended September 30, 2011, was $290,000 and $1,009,000, respectivelycompared to $437,000 and $1,369,000, respectively, for the threemonths and nine months ended September 30, 2010. Share-basedcompensation has been recognized as a component of salaries andbenefits expense in the accompanying Consolidated CondensedStatements of Income.Theestimated fair value of the stock options granted during 2011 andin prior years was calculated using a Black Scholes option pricingmodel.  The following summarizes the assumptions used inthe 2011 Black Scholes model:Risk-freeinterest rate2.74% Expectedprice volatility45.53% Dividendyield3.65% Forfeiturerate5.00% Weighted-averageexpected life, until exercise           6.91yearsThe BlackScholes model incorporates assumptions to value share-based awards.The risk-free rate of interest, for periods equal to the expectedlife of the option, is based on a U.S. government instrument over asimilar contractual term of the equity instrument. Expected pricevolatility is based on historical volatility of theCorporation’s common stock.  In addition, theCorporation generally uses historical information to determine thedividend yield and weighted-average expected life of the optionsuntil exercise. Separate groups of employees that have similarhistorical exercise behavior with regard to option exercise timingand forfeiture rates are considered separately for valuation andattribution purposes.Share-basedcompensation expense recognized in the Consolidated CondensedStatements of Income is based on awards ultimately expected to vestand is reduced for estimated forfeitures. Share-based compensationguidance requires forfeitures to be estimated at the time of grantand revised, if necessary, in subsequent periods, if actualforfeitures differ from those estimates. Pre-vesting forfeitureswere estimated to be approximately five percent for the nine monthsended September 30, 2011, based on historicalexperience.Thefollowing table summarizes the components of the Corporation'sshare-based compensation awards recorded as expense:  Three Months Ended  Nine Months Ended   September 30,  September 30,   2011  2010  2011  2010 Stock andESPP Options            Pre-taxcompensation expense $56  $143  $165  $487 Income taxbenefit  (7)  (20)  (8)  (51)Stock andESPP option expense, net of income taxes $49  $123  $157  $436 RestrictedStock Awards                Pre-taxcompensation expense $234  $294  $844  $882 Income taxbenefit  (76)  (103)  (289)  (309)Restrictedstock awards expense, net of income taxes $158  $191  $555  $573 TotalShare-Based Compensation:                Pre-taxcompensation expense $290  $437  $1,009  $1,369 Income taxbenefit  (83)  (123)  (297)  (360)Totalshare-based compensation expense, net of income taxes $207  $314  $712  $1,009  As ofSeptember 30, 2011, unrecognized compensation expense related tostock options and RSAs totaling $98,263 and $1,395,754,respectively, is expected to be recognized over weighted-averageperiods of 0.75 and 1.56 years, respectively.Stock optionactivity under the Corporation's stock option plans, as ofSeptember 30, 2011, and changes during the nine months endedSeptember 30, 2011, were as follows:  Number of Shares  Weighted-Average Exercise Price  Weighted Average Remaining Contractual Term (in Years)  Aggregate Intrinsic Value Outstandingat January 1, 2011  1,061,429  $23.01       Granted/Converted  52,298  $9.14       Cancelled  (75,291) $20.46       OutstandingSeptember 30, 2011  1,038,436  $22.51   4.63   39,730 Vested andExpected to Vest at September 30, 2011  1,038,436  $22.55   4.63   39,730 Exercisableat September 30, 2011  956,686  $23.81   4.25   0  Theweighted-average grant date fair value was $3.09 for stock optionsgranted during the nine months ended September 30,2011.Theaggregate intrinsic value in the table above represents the totalpre-tax intrinsic value (the difference between the Corporation'sclosing stock price on the last trading day of the first ninemonths of 2011 and the exercise price, multiplied by the number ofin-the-money options) that would have been received by the optionholders had all option holders exercised their stock options onSeptember 30, 2011.  The amount of aggregate intrinsicvalue will change based on the fair market value of theCorporation's common stock.  There were no stock optionsexercised during the first nine months of 2011.Thefollowing table summarizes information on unvested RSAs outstandingas of September 30, 2011:  Number of Shares  Weighted-Average Grant Date Fair Value UnvestedRSAs at January 1, 2011  272,737  $12.46 Granted  136,933  $8.93 Forfeited  (5,135) $8.83 Vested  (70,543) $23.37 UnvestedRSAs at September 30, 2011  333,992  $8.74 The grantdate fair value of ESPP options was estimated at the beginning ofthe July 1, 2011, quarterly offering period of approximately$36,000. The ESPP options vested during the three months endingSeptember 30, 2011, leaving no unrecognized compensation expenserelated to unvested ESPP options at September 30,2011. |

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| - Definition
The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5444-113901Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 93-6 -Paragraph 53 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 64, 65, A240 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 50 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6406099&loc=d3e25284-112666Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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