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Derivative Instruments - Summary of the Effect of Derivatives Designated as Cash Flow Hedging Instruments (Details) - Foreign exchange contract - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues
Derivative Instruments, Gain (Loss) [Line Items]
Net Gains/(Losses) Reclassified from AOCI into Operating Income (in millions)	$ 18.3	$ 118.6	$ (42.5)
Operating expenses
Derivative Instruments, Gain (Loss) [Line Items]
Net Gains/(Losses) Reclassified from AOCI into Operating Income (in millions)	3.3	(3.3)	0.2
Cash flows, revenue | Revenues
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments, net, pretax	(9.9)	2.9	10.8
Cash flows, operating expenses | Operating expenses
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments, net, pretax	$ 0.0	$ 0.2	$ (0.1)

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 4A
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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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-Publisher FASB
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