| **Accumulated Other Comprehensive Income (Tables)**            | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| **Equity [Abstract]**                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Schedule of Accumulated Other Comprehensive Income (Loss)      | The following table summarizes the changes in the balances of each component of accumulated other comprehensive income (loss), net of tax, as of June 30, 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(11,773) 281 1,169  (10,323)Amounts reclassified from accumulated other comprehensive income(317)  247 713 643Period change(12,090) 281 1,416 713 (9,680)Balance at June 30, 2013$5,814 $(2,991) $(1,236) $(16,766) $(15,179)                    Balance at December 31, 2011$18,244 $(3,168) $(1,841) $(16,837) $(3,602)Other comprehensive income before reclassifications1,212 (58) (749)  405Amounts reclassified from accumulated other comprehensive income(839)   729 (110)Period change373 (58) (749) 729 295Balance at June 30, 2012$18,617 $(3,226) $(2,590) $(16,108) $(3,307)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| 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 and six months ended June 30, 2013 and 2012: Amount Reclassified from Accumulated Other Comprehensive Income For the Three Months Ended June 30,  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$239 $502 Other income - net realized gains on sales of available for sale securitiesRelated income tax expense(84) (176) Income tax expense $155 $326        Unrealized gains (losses) on cash flow hedges (2)     Interest rate contracts$(192)  Interest expense - subordinated debentures and term loansRelated income tax benefit67  Income tax expense $(125)         Unrealized gains (losses) on defined benefit plans     Amortization of net loss and prior service costs$(112) $(322) Other expenses - salaries and employee benefitsRelated income tax benefit39 113 Income tax expense $(73) $(209)        Total reclassifications for the period, net of tax$(43) $117  Amount Reclassified from Accumulated Other Comprehensive Income For the Six Months Ended June 30,Details about Accumulated Other Comprehensive Income Components20132012Affected Line Item in the Statements of IncomeUnrealized gains (losses) on available for sale securities (1)Realized securities gains reclassified into income$487$1,291Other income - net realized gains on sales of available for sale securitiesRelated income tax expense(170)(452)Income tax expense$317$839Unrealized gains (losses) on cash flow hedges (2)Interest rate contracts$(380)Interest expense - subordinated debentures and term loansRelated income tax benefit133Income tax expense$(247)Unrealized gains (losses) on defined benefit plansAmortization of net loss and prior service costs$(1,097)$(1,123)Other expenses - salaries and employee benefitsRelated income tax benefit384394Income tax expense$(713)$(729)Total reclassifications for the period, net of tax$(643)110(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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| - Definition
[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).
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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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