Computation of Earnings Per Share (Schedule of Earnings Per Share) (Details) (USD $)
In Thousands, except Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Computation of earnings per share      
Average number of common shares outstanding for basic calculation 7,694,392 7,604,303 7,572,841
Average potential effect of shares in the Directors Plan 168,948 [1] 195,063 [1] 194,634 [1]
Average number of common shares outstanding used to calculate diluted earnings per common share 7,863,340 7,799,366 7,767,475
Net income $ 12,510 $ 12,206 $ 10,210
Earnings per share      
Basic $ 1.63 $ 1.61 $ 1.35
Diluted $ 1.59 $ 1.56 $ 1.31
[1] Exclusive of shares held in the Rabbi Trust