Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Consolidated Statements of Changes in Shareholders' Equity [Abstract]
Cash dividend declared (in dollars per share)	$ 0.0656	$ 0.0656
Stock options exercised (in shares)	278,500
Purchase of treasury stock (in shares)	213,356
Sale of treasury stock (in shares)	71,925	106,351

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.

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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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