Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Stockholders' Equity [Abstract]
Cash dividends declared	$ 1.60	$ 1.48	$ 1.40
Exercise of stock options	20,000	126,168	18,899
Purchase of treasury shares	650,799us-gaap_TreasuryStockSharesAcquired	0us-gaap_TreasuryStockSharesAcquired	237,535us-gaap_TreasuryStockSharesAcquired

Number of share options (or share units) exercised during the current period.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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

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

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

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