CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Consolidated Statements of Changes In Shareholders' Equity [Abstract]
Options exercised, shares	1,158,537	389,089	136,290
Conversion of common stock units, shares	11,851	15,084	15,715
Conversion of restricted stock units, shares	146,930	104,152	182,309
Cash dividends, per share	$ 0.78	$ 0.55	$ 0.46
Treasury stock, beginning balance, shares	22,943,925	22,028,030	21,813,196
Treasury stock, acquisition of shares	173,629	915,895	214,834
Treasury stock, ending balance, shares	23,117,554	22,943,925	22,028,030