CONSOLIDATED STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash dividends declared:
Dividends declared per common share (in dollars per share)	$ 1.16	$ 1.10	$ 1.06
Common stock issued under employee stock plan, tax benefits	$ 2,068	$ 1,825	$ 1,524