Earnings Per Comon Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Earnings Per Share [Abstract]
Net Income	$ 5,181		$ 5,288
Basic, in shares	12,031	[1]	12,005	[1]
Basic Earnings, in dollars per share	$ 0.43	[1]	$ 0.44	[1]
Dilutive Average Shares Attributable to Stock Options, in shares	18		25
Weighted Average Shares - Diluted, in shares	12,049	[1]	12,030	[1]
Diluted Earnings, in dollars per share	$ 0.43	[1]	$ 0.44	[1]
Antidilutive Securities Excluded from the Calculation of Earnings Per Share, in shares	129		132

[1] Share and Per Share Amounts have been restated for the September 2012 2% stock dividend.