Consolidated Condensed Statements Of Changes In Stockholders' Equity (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Consolidated Condensed Statements Of Changes In Stockholders' Equity [Abstract]
Change in pension plan assets and benefit obligations, Tax effect	$ 222
Unrealized net holding gain (loss) on cash flow hedge, tax	60	71
Unrealized net holding gain (loss) on securities available-for-sale, tax	$ (1,188)	$ (3,431)
Cash dividends on common stock per share	$ 0.94	$ 0.94

Tax effect of the appreciation (loss) in value of unsold available-for-sale securities attributable to the parent entity. Excludes amounts related to other than temporary impairment (OTTI) losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 810

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-URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569643-111683

+ Details