Consolidated Condensed Statements Of Changes In Stockholders' Equity (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Statement of Stockholders' Equity [Abstract]
Change in pension plan assets and benefit obligations, Tax effect	$ 0	$ 222
Unrealized net holding gain on cash flow hedge, tax	0	60
Unrealized net holding loss on securities available-for-sale, tax	$ (1,282)	$ (1,188)
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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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Research Bulletin (ARB)

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

+ Details