Income Taxes (Schedule Of Gross Unrecognized Tax Benefits Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance of liability as of January 1	$ 34.0	$ 39.8	$ 42.0	$ 46.4
Increase as a result of tax positions taken during a prior year	5.4	1.1	4.6
Decrease as a result of tax positions taken during a prior year	(0.4)	(0.5)	(1.5)
Increase as a result of tax positions taken during the current year	1.8	3.2	3.1
Decrease as a result of settlements with taxing authorities	(2.5)	0.0	(1.1)
Reduction as a result of a lapse of the statute of limitations	(10.1)	(6.0)	(9.5)
Balance of liability as of December 31	$ 34.0	$ 39.8	$ 42.0	$ 46.4

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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