Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Dividend declared: Common stock (per share)	$ 0.905	$ 0.833	$ 0.78
Stock options exercised (shares)	31,760	24,541	67,731
Restricted stock grants (shares)	6,323	5,055	2,070
Treasury Stock [Member]
Purchase of treasury stock (shares)	327	1,050	8,074

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