Derivative Financial Instruments - Summary of (Gains) Losses Related to Assets and Liabilities Denominated in Foreign Currencies (Detail) - Transaction and operations support - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Net realized non-U.S. dollar gain (loss)	$ 26.6	$ (7.4)	$ (5.8)
Net (loss) gain from the related forward contracts	(11.9)	11.2	10.2
Net gains from non-U.S. dollar transactions and related forward contracts	$ 14.7	$ 3.8	$ 4.4

Net gain losses from foreign currency transactions and related forward contracts.

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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 before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

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Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

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