Earnings Per Comon Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Earnings Per Share [Abstract]
Net Income	$ 5,207		$ 5,594		$ 10,388		$ 10,882
Basic, in shares	12,021	[1],[2]	11,994	[1],[2]	12,026	[1],[2]	12,000	[1],[2]
Basic Earnings, in dollars per share	$ 0.43	[1],[2]	$ 0.47	[1],[2]	$ 0.86	[1],[2]	$ 0.91	[1],[2]
Dilutive Average Shares Attributable to Stock Options, in shares	17	[1]	15	[1]	18	[1]	19	[1]
Weighted Average Shares - Diluted, in shares	12,038	[1],[2]	12,009	[1],[2]	12,044	[1],[2]	12,019	[1],[2]
Diluted Earnings, in dollars per share	$ 0.43	[1],[2]	$ 0.47	[1],[2]	$ 0.86	[1],[2]	$ 0.91	[1],[2]
Antidilutive Securities Excluded from the Calculation of Earnings Per Share, in shares	124	[1]	209	[1]	126	[1]	209	[1]

[1] All share and per share amounts have been adjusted for the September 2012 2% stock dividend

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