Consolidated Statements Of Shareholders' Equity (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Consolidated Statements Of Shareholders' Equity [Abstract]
Cash dividends declared per share	$ 1.36	$ 1.36	$ 1.36
Reissuance of treasury stock under incentive plan, net of shares surrendered in payment including tax benefit, shares	316,063	154,183	192,685
Common stock issued, shares	3,083,229	5,973,182
Treasury stock acquired, shares	900,000