Stock-Based Compensation (Schedule Of Fair Value Of The Restricted Stock Awards Granted During The Periods) (Details) (Restricted Stock [Member], USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options or shares granted	24,606	4,167	392,542	196,748
Estimated fair value (in millions)	$ 1.0	$ 0.2	$ 16.6	$ 10.3
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options or shares granted		4,167	367,936	196,748
Estimated fair value (in millions)		0.2	15.6	10.3
Percentage of shares granted expected to be distributed		95.00%	89.00%	93.00%
Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options or shares granted	24,606		24,606	31,500
Estimated fair value (in millions)	$ 1.0		$ 1.0	$ 0.7
Percentage of shares granted expected to be distributed	100.00%		100.00%