| **Disclosures About Fair Value of Assets and Liabilities (Tables)**                                                                                                                    | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| **Fair Value Disclosures [Abstract]**                                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| Fair Value Measurements of Assets and Liabilities Recognized in Consolidated Condensed Balance Sheets Measured at Fair Value                                                           | The following table presents the fair value measurements of assets and liabilities recognized in the Consolidated Condensed Balance Sheets measured at fair value on a recurring basis and the level within the fair value hierarchy in which the fair value measurements fall at September 30, 2013, and December 31, 2012.   Fair Value Measurements Using:September 30, 2013Fair ValueQuoted Prices in Active Markets for Identical Assets(Level 1)Significant OtherObservable Inputs(Level 2)SignificantUnobservableInputs(Level 3)Available for sale securities:    U.S. Government-sponsored agency securities$3,800 $3,800 State and municipal202,182 181,672$20,510U.S. Government-sponsored mortgage-backed securities398,169398,169 Corporate obligations484  484Equity securities1,706 1,7024Interest rate swap asset3,054 3,054 Interest rate cap421 421 Interest rate swap liability4,577 4,577   Fair Value Measurements Using:December 31, 2012Fair ValueQuoted Prices inActive Markets forIdentical Assets(Level 1)Significant Other Observable Inputs(Level 2)SignificantUnobservableInputs(Level 3)Available for sale securities:    U.S. Government-sponsored agency securities$4,640 $4,640 State and municipal158,194 140,094$18,100U.S. Government-sponsored mortgage-backed securities348,579 348,579 Corporate obligations224  224Equity securities1,706 1,7024Interest rate swap asset6,103 6,103Interest rate cap197 197Interest rate swap liability9,766 9,766                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Reconciliation of Beginning and Ending Balances of Recurring Fair Value Measurements Recognized in Consolidated Condensed Balance Sheets using Significant Unobservable Level 3 Inputs | The following is a reconciliation of the beginning and ending balances of recurring fair value measurements recognized in the Consolidated Condensed Balance Sheets using significant unobservable (Level 3) inputs for three and nine months ended September 30, 2013, and 2012.  Three Months Ended September 30, 2013Nine Months Ended September 30, 2013 Availablefor SaleSecuritiesInterestRate SwapAssetInterestRateCapInterest Rate SwapLiabilityAvailablefor SaleSecuritiesInterestRate SwapAssetInterestRateCapInterestRate SwapLiabilityBalance at beginning of the period$17,915$18,328Total realized and unrealized gains and losses:  Included in net income (loss)Included in other comprehensive income(486)(521)Purchases, issuances and settlementsTransfers in/(out) of Level 33,9053,905Principal payments/additions(336)(714)Ending balance at September 30, 2013$20,998$20,998 Three Months Ended September 30, 2012Nine Months Ended September 30, 2012 Availablefor Sale SecuritiesInterestRate SwapAssetInterestRateCapInterest Rate SwapLiabilityAvailablefor Sale SecuritiesInterestRate SwapAssetInterestRateCapInterestRate Swap LiabilityBalance at beginning of the period$19,740$20,838$5,241$424$(7,797)Total realized and unrealized gains and losses:     Included in net income (loss)(860)863Included in other comprehensive income(183)(944)481(15)Purchases, issuances and settlementsTransfers in/(out) of Level 3(4,862)(409)6,934Principal payments(1,132)(1,469) Ending balance at  September 30, 2012$18,425$18,425$—$—$—                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Transfer Between Levels 1, 2 and 3 and Reasons For Transfers                                                                                                                           | Transfer between Levels 1, 2 and 3 and the reasons for those transfers are as follows:  Three and Nine Months Ended September 30, 2013  Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs(Level 2) Significant Unobservable Inputs(Level 3) Reason for TransferTransfers to/(from) Level:       Available for sale securities  $(3,905) $3,905 Selected state and municipal securities were transferred from Level 2 to Level 3 due to limited availability of similar securities in active markets.   $(3,905) $3,905   Nine Months Ended September 30, 2012  Quoted Prices inActive Markets for Identical Assets (Level 1) Significant OtherObservable Inputs(Level 2) Significant Unobservable Inputs (Level 3)Reason for TransferTransfers to/(from) Level:    Interest rate swap asset $4,862$(4,862)The interest rate swap and cap instruments were transferred from Level 3 to Level 2 as of March 31, 2012 due to the availability of additional valuation information. These instruments are valued using widely accepted valuation techniques including discounted cash flow analysis using observable inputs such as contractual terms and LIBOR-based rate curves.Interest rate cap 409(409)Interest rate swap liability 6,934(6,934) $12,205$(12,205)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Description of Valuation Methodologies Used for Instruments Measured at Fair Value on a Non-Recurring Basis and Recognized in Consolidated Condensed Balance Sheets                    | The following table presents the fair value measurement of assets and liabilities measured at fair value on a nonrecurring basis and the level within the fair value hierarchy in which the fair value measurements fall at September 30, 2013, and December 31, 2012.   Fair Value Measurements UsingSeptember 30, 2013Fair ValueQuoted Prices inActive Markets forIdentical Assets(Level 1)Significant OtherObservableInputs(Level 2)Significant UnobservableInputs(Level 3)Impaired loans (collateral dependent)$8,874  $8,874Other real estate owned$8,220  $8,220    Fair Value Measurements UsingDecember 31, 2012Fair ValueQuoted Prices inActive Markets forIdentical Assets(Level 1)Significant OtherObservable Inputs(Level 2)Significant UnobservableInputs(Level 3)Impaired loans (collateral dependent)$17,703  $17,703Other real estate owned$7,684  $7,684                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements Other Than Goodwill                                                                             | The following table presents quantitative information about unobservable inputs used in recurring and nonrecurring Level 3 fair value measurements, other than goodwill, at September 30, 2013.  Fair ValueValuation TechniqueUnobservable InputsRangeState and municipal securities$20,510Discounted cash flowMaturity/Call date1 month to 10 yrs   Blend of US Muni BQ curveA- to BBB-   Discount rate1% - 5%        Corporate obligations/Equity securities$488Discounted cash flowRisk free rate3 month LIBOR   plus Premium for illiquidityplus 200bps        Impaired loans (collateral dependent)$8,874Collateral based measurementsDiscount to reflect current market conditions and ultimate collectability0% - 50%   Other real estate owned$8,220AppraisalsDiscount to reflect current market conditions0% - 20%                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Estimated Fair Values of Financial Instruments                                                                                                                                         | The following table presents estimated fair values of the Corporation’s financial instruments and the level within the fair value hierarchy in which the fair value measurements fall at September 30, 2013, and December 31, 2012.September 30, 2013(unaudited) CarryingAmountQuoted Prices in Active Marketsfor IdenticalAssetsSignificantOtherObservableInputsSignificant UnobservableInputs (Level 1)(Level 2)(Level 3)Assets:    Cash and due from banks$92,341$92,341  Interest-bearing time deposits18,87518,875  Investment securities available for sale606,341 $585,343$20,998Investment securities held to maturity307,794 303,37111,012Mortgage loans held for sale5,312 5,312 Loans2,859,233  2,822,465Federal Reserve Bank and Federal Home Loan Bank stock32,790 32,790 Interest rate swap and cap asset3,475 3,475 Interest receivable16,171 16,171 Liabilities:    Deposits$3,255,846$2,548,183$700,168 Borrowings:    Federal funds purchased115,938 115,938 Securities sold under repurchase agreements123,935 124,195 Federal Home Loan Bank advances172,292 173,449 Subordinated debentures and term loans111,849 63,391 Interest rate swap liability4,577 4,577 Interest payable1,155 1,155 December 31, 2012 CarryingAmountQuoted Prices in Active Marketsfor IdenticalAssetsSignificantOtherObservableInputsSignificant UnobservableInputs (Level 1)(Level 2)(Level 3)Assets:    Cash and due from banks$101,460$101,460  Interest-bearing time deposits38,44338,443  Investment securities available for sale513,343 $495,015$18,328Investment securities held to maturity361,020 366,59011,584Mortgage loans held for sale22,300 22,300 Loans2,832,843  2,852,614Federal Reserve Bank and Federal Home Loan Bank stock32,785 32,785 Interest rate swap and cap asset6,300 6,300Interest receivable16,367 16,367 Liabilities:    Deposits$3,346,383$2,478,706$865,793 Borrowings:    Federal funds purchased18,86218,862Securities sold under repurchase agreements141,828 142,318 Federal Home Loan Bank advances94,238 97,357 Subordinated debentures and term loans112,161 62,133 Interest rate swap liability9,766 9,766Interest payable1,841 1,841  |

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| - Definition
Fair Value, Assets And Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation
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| - Definition
Tabular disclosure of the inputs and valuation techniques used to measure fair value, and a discussion of changes in valuation techniques and related inputs, if any, applied during the period to each separate class of assets, liabilities, and financial instruments classified in shareholders' equity that are measured on a recurring and/or nonrecurring basis.
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Tabular disclosure of assets and liabilities by class, including financial instruments measured at fair value that are classified in shareholders' equity, if any, that are measured at fair value on a nonrecurring basis in periods after initial recognition (for example, impaired assets). Disclosures may include, but are not limited to: (a) the fair value measurements recorded and the reasons for the measurements and (b) the level within the fair value hierarchy in which the fair value measurements are categorized in their entirety (levels 1, 2, 3).
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Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities.
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Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).
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