Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Consolidated Statements of Changes in Shareholders' Equity
Stock option exercises/deferred stock unit conversions	144,203	491,728
Purchase of treasury stock, shares	29,823	3,406
Treasury stock issued/sold to the 401(k) stock purchase plan, shares		40,019
Common stock issued/sold to the 401( k) stock purchase plan, shares	22,680	89,743
Cash dividends, per share	$ 0.91	$ 0.88

Aggregate dividends paid during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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Number of new stock issued during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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Number of shares issued during the period as a result of the exercise of stock options.

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Number of treasury shares reissued during the period. Upon reissuance, these are common and preferred shares outstanding.

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Number of shares that have been repurchased during the period and are being held in treasury.

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