Derivative Instruments - Net Investment Hedges in Statements of Operations and Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative [Line Items]
Gains (losses) on foreign exchange forward contracts - cumulative translation adjustments, net of tax benefit	$ (33.8)	$ 3.3
Forward exchange forward contracts
Derivative [Line Items]
Gains (losses) on foreign exchange forward contracts - other income, net	0.3
Gains (losses) on foreign exchange forward contracts - cumulative translation adjustments, net of tax benefit	1.3
Gains (losses) on foreign exchange forward contracts - cumulative translation adjustments, tax liability	$ 0.4

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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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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

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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
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