CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY [Parenthetical] - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015
Dividends per share (in dollars per shares)	[1]	$ 0.60	$ 0.54
Exercise of stock options (in shares)		117,919	7,941
Excess tax benefit related to stock option plans (in dollars)		$ 266	$ 5

[1] Per share amounts for the periods ended September 30, 2015 have been adjusted to give effect to the 5% stock dividend paid during December 2015.