Stock-Based Compensation Plans (Schedule Of Future Share-Based Compensation Cost) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2013	$ 11.7
2014	7.8
2015	6.3
2016	5.5
2017	4.4
Thereafter	11.3
Total	47.0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2013	3.2
2014	2.3
2015	2.0
2016	1.8
2017	1.6
Thereafter	7.0
Total	17.9
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2013	8.5
2014	5.5
2015	4.3
2016	3.7
2017	2.8
Thereafter	4.3
Total	$ 29.1

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Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs Next Twelve Months

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