Derivative Financial Instruments - Fair Value of Open Foreign Currency Exchange Contracts (Detail) - Foreign Exchange Contracts [Member] - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022
Derivatives, Fair Value [Line Items]
Net fair value	$ (36,832)	$ (48,901)
Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Net fair value	(38,046)	(50,846)
Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Net fair value	1,214	1,945
Prepaid Expenses and Other Current Assets [Member] \| Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	968	1,226
Prepaid Expenses and Other Current Assets [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	10,586	10,808
Other Noncurrent Assets [Member] \| Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	331	0
Accrued Expenses and Other Current Liabilities [Member] \| Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability	(32,295)	(35,659)
Accrued Expenses and Other Current Liabilities [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability	(9,372)	(8,863)
Other Noncurrent Liabilities [Member] \| Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability	$ (7,050)	$ (16,413)

Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 9
-SubTopic 20
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483444/210-20-55-9

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-SubTopic 20
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483466/210-20-50-3

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-SubTopic 20
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483444/210-20-55-10

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-8

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- Definition

Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-10

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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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