Stock-Based Compensation Plans (Schedule Of Future Share-Based Compensation Cost) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remainder of 2013	$ 7.4
2014	7.6
2015	6.4
2016	5.7
2017	4.8
Thereafter	12.9
Total	44.8
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remainder of 2013	2.5
2014	2.6
2015	2.1
2016	1.9
2017	1.7
Thereafter	7.4
Total	18.2
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remainder of 2013	4.9
2014	5.0
2015	4.3
2016	3.8
2017	3.1
Thereafter	5.5
Total	$ 26.6

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Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Four Years

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Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs Remainder Of Fiscal Year

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