Income Taxes (Schedule Of Gross Unrecognized Tax Benefits Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance of liability as of January 1	$ 46.4	$ 46.5	$ 45.2	$ 40.7
Increase as a result of tax positions taken during a prior year	2.5	0.5	1.5
Decrease as a result of tax positions taken during a prior year	(1.5)	(7.3)	(2.1)
Increase as a result of tax positions taken during the current year	5.2	10.3	9.2
Decrease as a result of settlements with taxing authorities	(0.3)	(1.2)	0.0
Reduction as a result of a lapse of the statute of limitations	(6.0)	(1.0)	(4.1)
Balance of liability as of December 31	$ 46.4	$ 46.5	$ 45.2	$ 40.7

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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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 decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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