Stock-Based Compensation Plans (Schedule Of Future Share-Based Compensation Cost) (Details) $ in Millions	Dec. 31, 2016 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2017	$ 4.5
2018	3.2
2019	2.3
2020	1.8
2021	1.3
Thereafter	2.6
Total	15.7
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2017	2.0
2018	1.5
2019	1.2
2020	1.0
2021	0.9
Thereafter	2.5
Total	9.1
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2017	2.5
2018	1.7
2019	1.1
2020	0.8
2021	0.4
Thereafter	0.1
Total	$ 6.6

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

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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 In Three Years

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

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

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Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs Total

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