Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for doubtful accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 19.9	$ 16.9	$ 12.3
Charged/ (credited) to expense	18.3	7.1	9.5
Charged/(credited) to other accounts	0.2	0.2	(0.4)
Deductions from reserves	1.9	4.3	4.5
Balance at end of period	36.5	19.9	16.9
Valuation allowance-taxes
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	58.0	41.8	25.7
Charged/ (credited) to expense	(16.3)	16.2	27.4
Charged/(credited) to other accounts	0.0	0.0	0.0
Deductions from reserves	0.0	0.0	11.3
Balance at end of period	$ 41.7	$ 58.0	$ 41.8

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 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(Column B))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

Reference 2: 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(Column E))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

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

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

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