Stock-Based Compensation (Summary Of The Status Of Nonvested Share Awards) (Details)	9 Months Ended
	Sep. 30, 2015 $ / shares shares
Nonvested Share Awards [Roll Forward]
Nonvested, Shares, Beginning Balance	1,259,689
Granted, Shares	215,245
Vested, Shares	(141,877)
Forfeited, Shares	(15,936)
Nonvested, Shares, Ending Balance	1,317,121
Nonvested, Weighted Average Grant Date Fair Value, Beginning Balance | $ / shares	$ 34.41
Granted , Weighted Average Grant Date Fair Value | $ / shares	41.69
Vested , Weighted Average Grant Date Fair Value | $ / shares	30.11
Forfeited , Weighted Average Grant Date Fair Value | $ / shares	34.79
Nonvested , Weighted Average Grant Date Fair Value, Ending Balance | $ / shares	$ 36.05