| **Accumulated Other Comprehensive Income (Tables)**            | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
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| **Equity [Abstract]**                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Schedule of Accumulated Other Comprehensive Income (Loss)      | The following table summarizes the activity in accumulated other comprehensive income (loss), net of tax, for the three months ended March 31, 2013 and 2012: Accumulated Other Comprehensive Income Unrealized Gains (Losses) on Securities Available for Sale Unrealized Gains (Losses) on Securities Available for Sale for which a Portion of Other-Than-Temporary Impairment has been Recognized in Income Unrealized Gains (Losses) on Cash Flow Hedges Unrealized Gains (Losses) on Defined Benefit Plans TotalBalance at December 31, 2012$17,904 $(3,272) $(2,652) $(17,479) $(5,499)Other comprehensive income before reclassifications(2,115) 72 193  (1,850)Amounts reclassified from accumulated other comprehensive income(161)  122 640 601Period change(2,276) 72 315 640 (1,249)Balance at March 31, 2013$15,628 $(3,200) $(2,337) $(16,839) $(6,748)                    Balance at December 31, 2011$18,244 $(3,168) $(1,841) $(16,837) $(3,602)Other comprehensive income before reclassifications(20) (14) 304  270Amounts reclassified from accumulated other comprehensive income(513)   520 7Period change(533) (14) 304 520 277Balance at March 31, 2012$17,711 $(3,182) $(1,537) $(16,317) $(3,325)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| Reclassification out of Accumulated Other Comprehensive Income | The following table presents the reclassification adjustments out of accumulated other comprehensive income (loss) that were included in net income in the Consolidated Condensed Statements of Income for the three months ended March 31, 2013 and 2012: Amount Reclassified from Accumulated Other Comprehensive Income For the Three Months Ended March 31,  Details about Accumulated Other Comprehensive Income Components2013 2012 Affected Line Item in the Statements of IncomeUnrealized gains (losses) on available for sale securities (1)     Realized securities gains reclassified into income$248 $789 Other income - net realized gains on sales of available for sale securitiesRelated income tax expense(87) (276) Income tax expense $161 $513        Unrealized gains (losses) on cash flow hedges (2)     Interest rate contracts$(188)  Interest expense - subordinated debentures and term loansRelated income tax benefit66  Income tax expense $(122)         Unrealized gains (losses) on defined benefit plans     Amortization of net loss and prior service costs$(985) $(802) Other expenses - salaries and employee benefitsRelated income tax benefit345 282 Income tax expense $(640) $(520)        Total reclassifications for the period, net of tax$(601) $(7)  (1)  For additional detail related to unrealized gains (losses) on available for sale securities and related amounts reclassified from accumulated        other comprehensive income see NOTE 3. INVESTMENT SECURITIES.(2)  For additional detail related to unrealized gains (losses) on cash flow hedges and related amounts reclassified from accumulated other comprehensive income see NOTE 6. DERIVATIVE FINANCIAL INSTRUMENTS. |

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[Table Text Block] for Reclassification Out Of Accumulated Other Comprehensive Income [Table]
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No definition available.
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| - Definition
Tabular disclosure of the components of accumulated other comprehensive income (loss).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669686-108580
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