Goodwill and Other Intangible Assets (Pro Forma Financial Information and Acquisition Results) (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Pro Forma Financial Information and Acquisition Results [Abstract]
Business combinations, unaudited supplemental pro forma revenue	$ 2,015.3	$ 2,030.3	$ 5,474.0	$ 5,139.6
Business combinations, unaudited supplemental pro forma net income (loss)	127.8	122.9	293.7	235.7
Business combinations, consolidated acquisition-related revenue	41.7	18.4	116.9	141.0
Business combinations, consolidated acquisition-related income (loss)	$ 1.5	$ 0.9	$ (5.9)	$ (1.9)

No definition available.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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