Stock Option Plans (Summary of Status and Changes in Stock Option Plan) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Shares
Options outstanding, Beginning balance	687,043
Options granted			58,000
Options exercised	(118,823)	(61,677)	(67,916)
Options outstanding, Ending balance		687,043
Options exercisable at year end	568,220
Weighted Average Exercise Price
Options Outstanding, Weighted Average Exercise Price, Beginning balance	$ 10.70
Options Exercised, Weighted Average Exercise Price	$ 11.34
Options Outstanding, Weighted Average Exercise Price, Ending balance	$ 10.57	$ 10.70
Weighted- Average Remaining Contractual Life (in years)
Options Outstanding, Weighted-Average Remaining Contractual Life	6 years 6 months
Aggregate Intrinsic Value
Options Outstanding, Aggregate Intrinsic Value	$ 6,570,000