Valuation and Qualifying Accounts and Reserves (Schedule II) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Doubtful Accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	$ 45.9	$ 53.0	$ 40.5
Bad debt expense	53.1	38.2	42.7
Uncollectible accounts written off, net of recoveries	(62.5)	(45.3)	(30.2)
Ending balance	36.5	45.9	53.0
Deferred Tax Asset Valuation Allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	73.5	44.1	17.3
Additions (deductions)	7.4	10.6	(0.5)
Acquired balances	3.7	18.8	27.3
Ending balance	$ 84.6	$ 73.5	$ 44.1

SEC Schedule, 12-09, Valuation Allowances And Reserves, Additions (Deductions)

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- Definition

Valuation Allowance and Reserves, Deductions (Recoveries), Net

+ References

No definition available.

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- Definition

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

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from business combination.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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