Stock-Based Compensation Plans (Schedule Of Future Share-Based Compensation Cost) (Details) $ in Millions	Dec. 31, 2019 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2020	$ 4.7
2021	1.8
2022	1.0
2023	0.7
2024	0.5
Thereafter	0.5
Total	9.2
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2020	2.8
2021	0.6
2022	0.1
2023	0.0
2024	0.0
Thereafter	0.0
Total	3.5
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2020	1.9
2021	1.2
2022	0.9
2023	0.7
2024	0.5
Thereafter	0.5
Total	$ 5.7

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

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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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