Stock-Based Compensation Plans (Schedule Of Future Share-Based Compensation Cost) (Details) $ in Millions	Dec. 31, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2020	$ 2.4
2021	1.2
2022	0.8
2023	0.5
2024	0.3
Thereafter	0.2
Total	5.4
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2020	1.2
2021	0.3
2022	0.1
2023	0.0
2024	0.0
Thereafter	0.0
Total	1.6
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2020	1.2
2021	0.9
2022	0.7
2023	0.5
2024	0.3
Thereafter	0.2
Total	$ 3.8

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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