CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CAPITAL SURPLUS:
Cash dividends, per share	$ 0.60	$ 0.56	$ 0.52
RETAINED EARNINGS:
Cash dividends, per share	$ 0.60		$ 0.52