Stock-Based Compensation (Summary Of The Status Of Nonvested Share Awards) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014
Nonvested Share Awards [Roll Forward]
Nonvested, Shares, Beginning Balance	1,143,755
Granted, Shares	171,524
Vested, Shares	(73,330)
Forfeited, Shares	(15,494)
Nonvested, Shares, Ending Balance	1,226,455
Nonvested, Weighted Average Grant Date Fair Value, Beginning Balance	$ 34.27
Granted , Weighted Average Grant Date Fair Value	$ 44.52
Vested , Weighted Average Grant Date Fair Value	$ 28.25
Forfeited , Weighted Average Grant Date Fair Value	$ 40.19
Nonvested , Weighted Average Grant Date Fair Value, Ending Balance	$ 35.99