Consolidated Statement of Changes in Shareholders' Equity (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2012
Issuance of 1,437 shares for exercise of options, including tax effect	1,437
Purchase of 4,543 common shares	4,543
Cash dividends declared $0.475 per share	$ 0.475

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

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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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-Name Regulation S-X (SX)

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

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