Financial Instruments and Fair Value - Net Gain/Loss on Derivative Instruments (Details) - Cross-currency fixed interest rate swap - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Not Designated as Hedging Instrument \| Other Operating Income (Expense)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net gain (loss) on derivative instruments	$ (6.3)	$ 6.7	$ 21.7	$ (1.3)
Designated as Hedging Instrument \| Net Investment Hedging
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gain, net of tax	0.7	6.8	24.0	5.4
Designated as Hedging Instrument \| Interest Expense \| Net Investment Hedging
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Amount offsetting interest expense	$ 0.1	$ 6.1	$ 6.2	$ 12.2

Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Net Of Tax

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- Definition

Amount of gain (loss) from excluded component of derivative hedge, recognized in earnings. Excludes recognition under systematic and rational method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 45
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121577181&loc=SL110061172-113977

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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