Derivative Instruments - Net Investment Hedges in Statements of Operations and Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative [Line Items]
Cumulative translation adjustments	$ (12.4)	$ 10.3	$ (15.2)	$ (18.4)
Income tax effect	0.2	(0.5)	0.5	(0.3)
Forward Contracts
Derivative [Line Items]
Gain recognized in the statements of operations and comprehensive income, net of tax	(0.2)	(0.2)	(0.6)	(0.8)
Cumulative translation adjustments	0.6	(1.8)	1.5	(1.3)
Income tax effect	$ (0.2)	$ 0.5	$ (0.5)	$ 0.3

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.

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Amount, after tax and 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
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- Definition

Amount before tax, 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 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
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