Incentive Compensation Plans (Schedule of Stock Option Activity) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Non-vested stock options outstanding, Number of shares
Non-vested stock options outstanding, beginning balance	158,854	284,925	281,975
Stock options granted	142,000	40,000	146,000
Stock options vested	(78,958)	(125,071)	(142,050)
Stock options forfeited	(20,740)	(41,000)	(1,000)
Non-vested stock options outstanding, ending balance	201,156	158,854	284,925
Non-vested stock options outstanding, Weighted-average grant-date fair value
Non-vested stock options outstanding, Weighted-average grant-date fair value, beginning balance	$ 18.81	$ 15.56	$ 12.59
Stock options granted	$ 18.02	$ 20.60	$ 21.27
Stock options vested	$ 18.01	$ 15.31	$ 14.78
Stock options forfeited	$ 15.87	$ 16.68	$ 16.08
Non-vested stock options outstanding, Weighted-average grant-date fair value, ending balance	$ 18.83	$ 18.81	$ 15.56
Stock options outstanding, Number of shares
Stock options outstanding, beginning balance	647,050	720,100	605,600
Stock options granted	142,000	40,000	146,000
Stock options exercised	(55,625)	(72,050)	(27,500)
Stock options forfeited	(26,500)	(41,000)	(4,000)
Stock options outstanding, ending balance	706,925	647,050	720,100
Stock options outstanding, Weighted-average exercise price
Stock options outstanding, Weighted-average exercise price, beginning balance	$ 26.52	$ 25.19	$ 22.02
Stock options granted	$ 32.72	$ 36.66	$ 36.33
Stock options exercised	$ 15.25	$ 18.06	$ 13.64
Stock options forfeited	$ 27.67	$ 27.84	$ 32.07
Stock options outstanding, Weighted-average exercise price, ending balance	$ 28.61	$ 26.52	$ 25.19