CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Statement Of Stockholders Equity [Abstract]
Common stock dividends, per share	$ 0.56	$ 0.46
Stock option plan, shares	13,834	10,964
Employee stock purchase plan, shares	18,404	19,971
Restricted stock, shares	54,535	48,819