Consolidated Statement of Changes in Shareholders' Equity (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Issuance of shares for exercise of options	461	381	2,079
Issuance of shares for employee stock purchase plan	92	0	0
Purchase of common shares	4,710us-gaap_TreasuryStockSharesAcquired	1,055us-gaap_TreasuryStockSharesAcquired	5,567us-gaap_TreasuryStockSharesAcquired
Cash dividends declared	$ 1.04	$ 0.78	$ 0.64

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

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Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

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

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