Derivative Instruments - Net Investment Hedges in Statements of Operations and Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative [Line Items]
Gains (losses) on foreign exchange forward contracts - cumulative translation adjustments, net of tax benefit	$ 4.9	$ (3.9)	$ (28.9)	$ (0.6)
Forward exchange forward contracts
Derivative [Line Items]
Gains (losses) on foreign exchange forward contracts - other income, net	0.2	0.1	0.5	0.1
Gains (losses) on foreign exchange forward contracts - cumulative translation adjustments, net of tax benefit	(0.8)	(0.2)	0.5	(0.2)
Gains (losses) on foreign exchange forward contracts - cumulative translation adjustments, tax (benefit) expense	$ (0.2)	$ (0.1)	$ 0.2	$ (0.1)

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No definition available.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (a)
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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount, after tax, of reclassification from accumulated other comprehensive income (AOCI) of gain (loss) from increase (decrease) in fair value of net investment hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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