Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Consolidated Statements of Changes in Shareholders' Equity (Unaudited) [Abstract]
Cash dividend declared (in dollars per share)	$ 0.1969	$ 0.1969
Stock options exercised (in shares)	347,500	147,630
Purchase of treasury stock (in shares)	251,646	111,906
Sale of treasury stock (in shares)	231,750	316,337

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

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is 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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