Consolidated Statements Of Changes In Stockholders' Equity (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Consolidated Statements Of Changes In Stockholders' Equity [Abstract]
Change in funded status of pension plan, tax	$ (1,307)	$ 3,383	$ (8,735)
Unrealized net holding gain (loss) on cash flow hedge, net of tax	(53)	159	(678)
Unrealized net holding gain (loss) on securities available-for-sale, tax portion	(8,078)	(815)	16,522
Cash dividends on common stock per share	$ 3.76	$ 3.76	$ 3.77
SFAS No. 158 measurement date adjustment, tax			$ (178)

Common stock cash dividends per share.

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- Definition

Effect on retained earnings accumulated deficit due to change in measurement date tax.

+ References

No definition available.

+ Details

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- Definition

Tax effect of the gross appreciation or the gross loss, net of reclassification adjustment, in the change in value of available for sale securities during the period that is attributable to the parent entity.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 29, 30

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- Definition

Tax effect of the change in accumulated other comprehensive income, that is, the tax effect on items included in other comprehensive income during the period that is attributable to the parent entity.

+ References

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- Definition

The tax effect of the amount of the change in the additional minimum pension liability not yet recognized pursuant to FAS 87 as a net periodic pension cost. If the additional pension liability required to be recognized exceeds the unrecognized prior service costs, then the excess (which is the net loss not yet recognized as net periodic pension cost) is to be recorded as a separate component in other comprehensive income, before adjusting for tax effects. In a subsequent measurement, the elimination or adjustment to the amount of the minimum pension liability recorded in accumulated other comprehensive income is included in this line. Eliminated upon adoption of FAS 158.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

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