Stock-Based Compensation (Summary Of The Status Of Nonvested Share Awards) (Details) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013
Nonvested Share Awards [Roll Forward]
Nonvested, Shares, Beginning Balance		882,803
Granted, Shares	42,674	397,596
Vested, Shares		(42,125)
Forfeited, Shares		(16,609)
Canceled, Shares		(115,497)
Nonvested, Shares, Ending Balance	1,106,168	1,106,168
Nonvested, Weighted Average Grant Date Fair Value, Beginning Balance		$ 34.62
Granted , Weighted Average Grant Date Fair Value		$ 38.42
Vested , Weighted Average Grant Date Fair Value		$ 34.88
Forfeited , Weighted Average Grant Date Fair Value		$ 33.77
Canceled, Weighted Average Grant Date		$ 35.32
Nonvested , Weighted Average Grant Date Fair Value, Ending Balance	$ 35.91	$ 35.91