| **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, 2016, and December 31, 2015.  Fair Value Measurements Using:September 30, 2016Fair 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$101   $101  State and municipal369,050   363,643 $5,407U.S. Government-sponsored mortgage-backed securities304,580   304,580  Corporate obligations31     31Equity securities2,016   2,012 4Interest rate swap asset12,102   12,102  Interest rate cap4   4  Interest rate swap liability16,535   16,535    Fair Value Measurements Using:December 31, 2015Fair 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$104 $104 State and municipal305,911 300,014$5,897U.S. Government-sponsored mortgage-backed securities346,266 346,266 Certificates of deposit2,176   2,176  Corporate obligations31  31Equity securities3,912 3,9084Interest rate swap asset4,938 4,938Interest rate cap36 36Interest rate swap liability8,070 8,070                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| 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 the three and nine months ended September 30, 2016 and 2015.  Available for Sale Securities Three Months Ended Nine Months ended September 30, 2016 September 30, 2015 September 30, 2016 September 30, 2015Balance at beginning of the period$5,564 $6,028 $5,932 $6,646Total realized and unrealized gains and losses:       Included in net income       Included in other comprehensive income(45) 24 52 165Purchases, issuances and settlements       Transfers in/(out) of Level 3       Principal payments(77) (156) (542) (915)Ending balance $5,442 $5,896 $5,442 $5,896                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| 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, 2016, and December 31, 2015.  Fair Value Measurements UsingSeptember 30, 2016Fair ValueQuoted Prices inActive Markets forIdentical Assets(Level 1)Significant OtherObservableInputs(Level 2)Significant UnobservableInputs(Level 3)Impaired loans (collateral dependent)$15,763  $15,763Other real estate owned2,213  2,213    Fair Value Measurements UsingDecember 31, 2015Fair ValueQuoted Prices inActive Markets forIdentical Assets(Level 1)Significant OtherObservable Inputs(Level 2)Significant UnobservableInputs(Level 3)Impaired loans (collateral dependent)$7,066  $7,066Other real estate owned5,529  5,529                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| 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, 2016 and December 31, 2015.September 30, 2016Fair ValueValuation TechniqueUnobservable InputsRange                  (Weighted-Average)State and municipal securities$5,407Discounted cash flowMaturity/Call date1 month to 20 yrs   Blend of US Municipal Bank Qualified curveA- to BBB-   Discount rate.69% - 5%        Corporate obligations and Equity securities$35Discounted cash flowRisk free rate3 month LIBOR   plus premium for illiquidityplus 200bps        Impaired loans (collateral dependent)$15,763Collateral based measurementsDiscount to reflect current market conditions and ultimate collectability0% - 10%                                        (1%)   Other real estate owned$2,213AppraisalsDiscount to reflect current market conditions0% - 10%                               (4%)December 31, 2015Fair Value Valuation Technique Unobservable Inputs Range                  (Weighted-Average)State and municipal securities$5,897 Discounted cash flow Maturity/Call date 1 month to 15 yrs     Blend of US Municipal Bank Qualified curve A- to BBB-     Discount rate .80% - 5%        Corporate obligations and Equity securities$35 Discounted cash flow Risk free rate 3 month LIBOR     plus premium for illiquidity plus 200bps        Impaired loans (collateral dependent)$7,066 Collateral based measurements Discount to reflect current market conditions and ultimate collectability 0% - 50%                                        (2%)        Other real estate owned$5,529 Appraisals Discount to reflect current market conditions 0% - 20%                               (2%)                                                                                                                                                                                                                                                                                                         |
| 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, 2016, and December 31, 2015.September 30, 2016 CarryingAmountQuoted Prices in Active Marketsfor IdenticalAssetsSignificantOtherObservableInputsSignificant UnobservableInputs (Level 1)(Level 2)(Level 3)Assets:    Cash and cash equivalents$99,602$99,602  Interest-bearing time deposits33,80333,803  Investment securities available for sale675,813 $670,371$5,442Investment securities held to maturity624,615 631,25515,791Loans held for sale1,482 1,482 Loans4,910,388  4,871,640Federal Home Loan Bank stock18,044 18,044 Interest rate swap and cap asset12,106 12,106 Interest receivable23,652 23,652 Liabilities:    Deposits$5,444,240$4,290,400$1,143,837 Borrowings:  Federal funds purchased58,358   58,358  Securities sold under repurchase agreements138,671 138,656 Federal Home Loan Bank advances297,022 295,834 Subordinated debentures and term loans128,288 105,604 Interest rate swap liability16,535 16,535 Interest payable3,733 3,733 December 31, 2015 CarryingAmountQuoted Prices in Active Marketsfor IdenticalAssetsSignificantOtherObservableInputsSignificant UnobservableInputs (Level 1)(Level 2)(Level 3)Assets:    Cash and cash equivalents$102,170$102,170  Interest-bearing time deposits32,31532,315  Investment securities available for sale658,400 $652,468$5,932Investment securities held to maturity618,599 598,08234,298Loans held for sale9,894 9,894 Loans4,631,369  4,539,940Federal Reserve Bank and Federal Home Loan Bank stock37,633 37,633 Interest rate swap and cap asset4,974 4,974Interest receivable24,415 24,415 Liabilities:    Deposits$5,289,647$4,095,004$1,177,142 Borrowings:    Federal funds purchased49,72149,721Securities sold under repurchase agreements155,325 155,325 Federal Home Loan Bank advances235,652 236,375 Subordinated debentures and term loans127,846 103,643 Interest rate swap liability8,070 8,070Interest payable3,092 3,092  |

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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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| - Definition
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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