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Derivative Financial Instruments - Effect on Statement of Comprehensive Income and Statement of Income (Details) - Designated as Hedging Instrument - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	$ (1.9)	$ 0.3	$ (0.9)	$ 13.8
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings	0.4	0.1	1.4	0.4
Gain (Loss) Recognized in Earnings from Excluded Components	0.0	0.0	0.0	2.8
Forward foreign currency contracts | Net Investment Hedging
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	(2.0)	0.4	(1.6)	64.9
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings	0.4	0.1	1.4	0.4
Gain (Loss) Recognized in Earnings from Excluded Components	0.0	0.0	0.0	2.8
Put options | Net Investment Hedging
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income			0.0	(47.7)
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings			0.0	0.0
Gain (Loss) Recognized in Earnings from Excluded Components			0.0	0.0
Call options | Net Investment Hedging
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income			0.0	(1.3)
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings			0.0	0.0
Gain (Loss) Recognized in Earnings from Excluded Components			0.0	0.0
Interest rate swap | Cash Flow Hedging
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	0.1	(0.1)	0.7	(2.1)
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings	0.0	0.0	0.0	0.0
Gain (Loss) Recognized in Earnings from Excluded Components	$ 0.0	$ 0.0	$ 0.0	$ 0.0

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Other Comprehensive Income (Loss), Net Investment And Cash Flow Hedge, Gain (Loss), Before Reclassification And Tax

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
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Amount, before tax and after adjustments, of gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method.

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