The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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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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The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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Maximum period of time the entity is hedging its exposure to variability in future cash flows for forecasted transactions, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes forecasted transactions related to payment of variable interest on existing financial instruments.

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

+ References

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Derivative Financial Instruments - Narrative (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Net foreign exchange contract gains (losses) reclassified from AOCI	$ 0.0	$ 0.0	$ 0.0
Maximum length of time being hedged for exposure to variability in future cash flows of forecasted foreign currency denominated transactions	23 months
Net investment hedge losses recognized in AOCI	$ 178.7	$ (59.7)
Foreign Currency Denominate
Derivative [Line Items]
Estimated net gain (loss) to be reclassified into earnings within the next twelve months relating to cash flow hedges	3.2
Foreign Currency Denominated Investment Securities
Derivative [Line Items]
Estimated net gain (loss) to be reclassified into earnings within the next twelve months relating to cash flow hedges	83.1
Available-for-sale Securities
Derivative [Line Items]
Estimated net gain (loss) to be reclassified into earnings within the next twelve months relating to cash flow hedges	$ 0.1