Consolidated Statement of Changes in Stockholders' Equity (Parenthetical) (USD $)	9 Months Ended
	Sep. 30, 2013
Cash dividends per share	$ 0.28	[1]
Purchase of treasury stock, shares	44,828
Reissuance of treasury stock for stock option exercises, shares	111,077
Treasury Stock [Member]
Purchase of treasury stock, shares	44,828
Reissuance of treasury stock for stock option exercises, shares	111,077
Retained Earnings [Member]
Cash dividends per share	$ 0.28	[1]
Reissuance of treasury stock for stock option exercises, shares	111,077

[1] Outstanding shares and per share data have been adjusted to reflect the six-for-five stock split declared April 16, 2013.