Earnings Per Share (Reconciliations And Calculations Of Basic And Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Earnings Per Share [Abstract]
Net income	$ 15,194	$ 14,620	$ 15,461
Weighted average common shares outstanding	6,259,000	6,212,000	6,167,000
Dilutive effect of common stock equivalents	12,000	12,000	4,000
Weighted average common and common equivalent shares outstanding	6,271,000	6,224,000	6,171,000
Basic earnings per common share	$ 2.43	$ 2.35	$ 2.51
Diluted earnings per common share	$ 2.42	$ 2.35	$ 2.51
Average stock options outstanding which were not included in the calculation of diluted earnings per share		7,500	44,478