Stock Options and Incentive Plans (Schedules of Stock Option Activity) (Details) (Employee Stock Option [Member], USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Employee Stock Option [Member]
Shares
Shares under option	507,313	597,313	639,163
Options canceled		23,300	400
Options exercised	278,780	66,700	41,450
Shares under option at December 31	228,533	507,313	597,313
Options exercisable at December 31	228,533	507,313	597,313
Weighted Average Exercise Price
Shares under option January 1	$ 19.45	$ 19.54	$ 19.51
Options granted
Options canceled		$ 21.23	$ 20.54
Options exercised	$ 19.87	$ 19.65	$ 19.03
Shares under option December 31	$ 18.94	$ 19.45	$ 19.54
Options exercisable December 31	$ 18.94	$ 19.45	$ 19.54