Derivative Financial Instruments - Additional Information (Detail) - USD ($)	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Derivative Instruments, Gain (Loss) [Line Item]
Maximum amount of loss due to credit risk	$ 4,682
Maximum length of time hedged in cash flow hedges	3 years
Maturity period of significant portion of forward and option contracts outstanding	12 months
Changes in fair value of cash flow hedges, net of tax	$ (32,655,000)	$ (75,226,000)	$ 24,239,000
Typical maturity period of other risk management derivatives	less than 12 months
Foreign Exchange Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Item]
Net unrealized (losses) gains from cash flow hedges recognized in other comprehensive (loss) income	$ (35,654,000)	(78,465,000)	23,720,000
Changes in fair value of cash flow hedges, net of tax	(32,655,000)	$ (75,226,000)	$ 24,239,000
Foreign currency cash flow hedge, reclassified into earnings during fiscal year 2023	$ 29,499,000

A description of typical maturity period of other risk management derivatives.

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- Definition

The value of maximum amount of loss due to credit risk.

+ References

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- Definition

Other Comprehensive Income (Losses), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax

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No definition available.

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- Definition

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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- Definition

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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- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

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- Definition

Amount, after tax and before 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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