Fair Value Measurements (Financial Assets And Liabilities Carried At Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Assets:
Available-for-sale debt securities	$ 38.3	$ 45.4
Investment in equity securities	148.9
Liabilities:
Deferred compensation plans	60.9	62.9
Quoted Prices in Active Market (Level 1)
Assets:
Available-for-sale debt securities	0.0	0.0
Investment in equity securities	0.0
Liabilities:
Deferred compensation plans	0.0	0.0
Significant Other Observable Inputs (Level 2)
Assets:
Available-for-sale debt securities	38.3	45.4
Investment in equity securities	0.0
Liabilities:
Deferred compensation plans	60.9	62.9
Significant Unobservable Inputs (Level 3)
Assets:
Available-for-sale debt securities	0.0	0.0
Investment in equity securities	148.9
Liabilities:
Deferred compensation plans	$ 0.0	$ 0.0

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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-Publisher FASB
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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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