| **Disclosures About Fair Value of Assets and Liabilities (Tables)**                                                                                                                    | 6 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 June 30, 2014, and December 31, 2013.   Fair Value Measurements Using:June 30, 2014Fair ValueQuoted Prices in Active Markets for Identical Assets(Level 1)Significant OtherObservable Inputs(Level 2)SignificantUnobservableInputs(Level 3)Available for sale securities:       U.S. Treasury$16,013   $16,013  U.S. Government-sponsored agency securities3,277   3,277  State and municipal246,707   239,972 $6,735U.S. Government-sponsored mortgage-backed securities346,687   346,687  Corporate obligations794     794Equity securities1,706   1,702 4Interest rate swap asset2,763   2,763  Interest rate cap202   202  Interest rate swap liability4,814   4,814    Fair Value Measurements Using:December 31, 2013Fair ValueQuoted Prices inActive Markets forIdentical Assets(Level 1)Significant Other Observable Inputs(Level 2)SignificantUnobservableInputs(Level 3)Available for sale securities:    U.S. Treasury$15,973   $15,973  U.S. Government-sponsored agency securities3,545 3,545 State and municipal230,987 223,752$7,235U.S. Government-sponsored mortgage-backed securities281,252 281,252 Corporate obligations2,738  2,738Equity securities1,706 1,7024Interest rate swap asset3,619 3,619Interest rate cap390 390Interest rate swap liability3,953 3,953                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| 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 six months ended June 30, 2014, and 2013.  Available for Sale Securities Three Months EndedJune 30, 2014 Three Months Ended June 30, 2013 Six Months Ended June 30, 2014 Six Months Ended June 30, 2013Balance at beginning of the period$11,494 $17,678 $9,977 $18,328Total realized and unrealized gains and losses:       Included in net income     Included in other comprehensive income835 140 2,893 (35)Purchases, issuances and settlements     Transfers in/(out) of Level 3    Principal payments(4,796) 97 (5,337) (378)Ending balance $7,533 $17,915 $7,533 $17,915                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| 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 June 30, 2014, and December 31, 2013.   Fair Value Measurements UsingJune 30, 2014Fair ValueQuoted Prices inActive Markets forIdentical Assets(Level 1)Significant OtherObservableInputs(Level 2)Significant UnobservableInputs(Level 3)Impaired loans (collateral dependent)$12,049  $12,049Other real estate owned$5,047  $5,047    Fair Value Measurements UsingDecember 31, 2013Fair ValueQuoted Prices inActive Markets forIdentical Assets(Level 1)Significant OtherObservable Inputs(Level 2)Significant UnobservableInputs(Level 3)Impaired loans (collateral dependent)$12,117  $12,117Other real estate owned$6,877  $6,877                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| 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 June 30, 2014.  Fair ValueValuation TechniqueUnobservable InputsRange                  (Weighted-Average)State and municipal securities$6,735Discounted cash flowMaturity/Call date1 month to 18 yrs   Blend of US Muni BQ curveA- to BBB-   Discount rate1% - 6%        Corporate obligations/Equity securities$798Discounted cash flowRisk free rate3 month LIBOR   plus Premium for illiquidityplus 200bps        Impaired loans (collateral dependent)$12,049Collateral based measurementsDiscount to reflect current market conditions and ultimate collectability0% - 50%                                        (1%)   Other real estate owned$5,047AppraisalsDiscount to reflect current market conditions0% - 20%                               (5%)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| 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 June 30, 2014, and December 31, 2013.June 30, 2014(unaudited) CarryingAmountQuoted Prices in Active Marketsfor IdenticalAssetsSignificantOtherObservableInputsSignificant UnobservableInputs (Level 1)(Level 2)(Level 3)Assets:    Cash and due from banks$115,891$115,891  Interest-bearing time deposits27,85627,856  Investment securities available for sale615,184 $607,651$7,533Investment securities held to maturity598,903 577,25134,911Mortgage loans held for sale7,370 7,370 Loans3,654,366  3,622,231Federal Reserve Bank and Federal Home Loan Bank stock43,127 43,127 Interest rate swap and cap asset2,965 2,965 Interest receivable18,341 18,341 Liabilities:    Deposits$4,329,610$3,292,460$1,019,785 Borrowings:  Federal funds purchased100,000 100,000 Securities sold under repurchase agreements133,137 133,150 Federal Home Loan Bank advances220,765 221,342 Subordinated debentures and term loans126,874 84,090 Interest rate swap liability4,814 4,814 Interest payable2,489 2,489 December 31, 2013 CarryingAmountQuoted Prices in Active Marketsfor IdenticalAssetsSignificantOtherObservableInputsSignificant UnobservableInputs (Level 1)(Level 2)(Level 3)Assets:    Cash and due from banks$109,434$109,434  Interest-bearing time deposits55,06955,069  Investment securities available for sale536,201 $526,224$9,977Investment securities held to maturity559,378 525,99834,849Mortgage loans held for sale5,331 5,331 Loans3,564,539  3,506,615Federal Reserve Bank and Federal Home Loan Bank stock38,990 38,990 Interest rate swap and cap asset4,009 4,009Interest receivable18,672 18,672 Liabilities:    Deposits$4,231,468$3,082,117$934,937 Borrowings:    Federal funds purchased125,645125,645Securities sold under repurchase agreements148,672 148,852 Federal Home Loan Bank advances122,140 122,962 Subordinated debentures and term loans126,807 82,607 Interest rate swap liability3,953 3,953Interest payable1,771 1,771  |

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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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| - Definition
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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| - Definition
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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