| **Fair Value of Financial Instruments (Tables)**                                                                                                                                       | 12 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 accompanying balance sheets measured at fair value on a recurring basis and the level within the ASC 820-10 fair value hierarchy in which the fair value measurements fall at December 31, 2012 and 2011.   Fair Value Measurements Using:   Quoted Prices in ActiveMarkets for Identical Assets Significant Other Observable Inputs SignificantUnobservable InputsDecember 31, 2012Fair Value (Level 1) (Level 2) (Level 3)U.S. Government-sponsored agency securities$4,640$4,640State and municipal158,194140,094$18,100U.S. Government-sponsored mortgage-backed securities348,579348,579Corporate obligations224224Equity securities1,7061,7024Interest rate swap asset6,1036,103Interest rate cap197197Interest rate swap liability9,7669,766   Fair Value Measurements Using:   Quoted Prices in ActiveMarkets for Identical Assets Significant Other Observable Inputs SignificantUnobservable InputsDecember 31, 2011Fair Value (Level 1) (Level 2) (Level 3)U.S. Government-sponsored agency securities$117 $117 State and municipal147,353 126,712$20,641U.S. Government-sponsored mortgage-backed securities368,998 368,998 Corporate obligations193  193Equity securities1,830 1,8264Interest rate swap asset5,241  5,241Interest rate cap424  424Interest rate swap liability7,797  7,797                                                                                                                                                                                                                                                                                                                                                                      |
| 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 accompanying balance sheet using significant unobservable Level 3 inputs for year ended December 31, 2012 and 2011. Year Ended December 31, 2012 Available forSale Securities Interest RateSwap Asset Interest Rate Cap Interest RateSwap LiabilityBeginning Balance$20,838$5,241$424$7,797Total realized and unrealized gains and lossesIncluded in net income(860)(863)Included in other comprehensive income(1,141)481(15)Purchases, issuances, and settlementsTransfers in/(out) of Level 3(4,862)(409)(6,934)Principal payments(1,369)Ending balance$18,328 Year Ended December 31, 2011 Available forSale Securities Interest RateSwap Asset InterestRate Cap Interest RateSwap LiabilityBeginning Balance$186 $4,002 $1,109 $3,876Total realized and unrealized gains and losses       Included in net income(400) 3,827   3,921Included in other comprehensive income2,029 (2,588) (685)  Purchases, issuances, and settlements       Transfers in/(out) of Level 318,711      Principal payments312      Ending balance$20,838 $5,241 $424 $7,797                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Transfer Between Levels 1, 2 and 3 and Reasons For Transfers                                                                                                                           | TRANSFERS BETWEEN LEVELS Quoted Prices in ActiveMarkets for Identical AssetsSignificant Other Observable InputsSignificantUnobservable Inputs(Level 1)(Level 2)(Level 3)Reason for Transfer Transfers to/(from) Level: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 swap asset$4,862$(4,862)Interest rate cap409(409)Interest rate swap liability6,934(6,934)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Description of Valuation Methodologies Used for Instruments Measured at Fair Value on a Non-Recurring Basis and Recognized in Consolidated Condensed Balance Sheets                    | Following is a description of valuation methodologies used for instruments measured at fair value on a non-recurring basis and recognized in the accompanying balance sheet, as well as the general classification of such instruments pursuant to the valuation hierarchy for year ended December 31, 2012 and 2011.  Fair Value Measurements Using  Quoted Prices in ActiveMarkets for Identical AssetsSignificant Other Observable InputsSignificantUnobservable InputsDecember 31, 2012Fair Value(Level 1)(Level 2)(Level 3)Impaired Loans (collateral dependent)$17,703  $17,703Other real estate owned $7,684  $7,684  Fair Value Measurements Using  Quoted Prices in ActiveMarkets for Identical AssetsSignificant Other Observable InputsSignificantUnobservable InputsDecember 31, 2011Fair Value(Level 1)(Level 2)(Level 3)Impaired Loans (collateral dependent)$22,885  $22,885Other real estate owned$7,882  $7,882                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| 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 December 31, 2012Fair ValueValuation TechniqueUnobservable InputsRangeState and municipal securities$18,100Discounted cash flowMaturity Call DateBlend of US Muni BQ curveDiscount rate1 month to 11 yearsA- to BBB-1% - 4%Corporate obligations/Equity securities$228Discounted cash flowRisk free rateplus Premium for illiquidity3 month LIBORplus 200 bpsImpaired loans (collateral dependent)$17,703Collateral based measurementsDiscount to reflect current market conditions and ultimate collectability0% - 50%Other real estate owned$7,684AppraisalsDiscount 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 December 31, 2012, and December 31, 2011. 2012 CarryingAmountQuoted Prices in Active Markets for Identical Assets (Level 1)Significant Other Observable Inputs(Level 2)Significant Unobservable Inputs(Level 3)Assets at December 31:   Cash and cash equivalents$101,460$101,460Interest-bearing time deposits38,44338,443Investment securities available for sale513,343$495,015$18,328Investment securities held to maturity361,020366,59011,584Mortgage loans held for sale22,30022,300Loans2,832,8432,852,614FRB and FHLB stock32,78532,785Interest rate swap asset6,3006,300Interest receivable16,36716,367Liabilities at December 31:Deposits$3,346,383$2,478,706$865,793Borrowings:Federal funds purchased18,86218,862Securities sold under repurchase agreements141,828142,318FHLB Advances94,23897,357Subordinated debentures and term loans112,16162,133Interest rate swap liability9,7669,766Interest payable1,8411,841 2011 CarryingAmountQuoted Prices in Active Markets for Identical Assets (Level 1)Significant Other Observable Inputs(Level 2)Significant Unobservable Inputs(Level 3)Assets at December 31:   Cash and cash equivalents$73,312$73,312Interest-bearing time deposits52,85152,851Investment securities available for sale518,491$497,653$20,838Investment securities held to maturity427,909428,73713,732Mortgage loans held for sale17,86417,864Loans2,642,5172,658,227FRB and FHLB stock31,27031,270Interest rate swap asset5,6655,665Interest receivable17,72317,723Liabilities at December 31:Deposits$3,134,655$2,195,679$944,078Borrowings:Securities sold under repurchase agreements156,305157,342FHLB Advances138,095141,693Subordinated debentures and term loans194,974142,632Interest rate swap liability7,7977,797Interest payable2,9252,925 |

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| - Definition
Fair Value, Assets And Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation
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Transfers In And Out Of Each Of Valuation Levels Of Fair Values Table
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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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| - Definition
Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such certain disclosures about the financial instruments, assets, and liabilities include: (1) the fair value of the required items together with their carrying amounts (as appropriate) and (2) the methodology and assumptions used in developing such estimates of fair value.
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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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