Condensed Consolidated Statements of Income Parenthetical (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
Average common shares outstanding	13,021	[1]	12,885	[1]	13,013	[1]	12,888	[1]
Cash dividends declared	$ 3,912		$ 3,525		$ 7,833		$ 7,053
Scenario, Previously Reported [Member]
Average common shares outstanding			11,714				11,716

[1] (A)Adjusted for the declaration of a ten percent (10%) stock dividend in 2011, shares related to which were issued in February 2012. Prior to the adjustment, the average common shares outstanding were 11,714 and 11,716 for the three and six months ended June 30, 2011, respectively.