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Derivatives - Details of Derivatives Held to Manage Foreign Currency Risk (Detail)		Sep. 30, 2025 USD ($)	Sep. 30, 2025 EUR (€)	Sep. 30, 2024 USD ($)	Sep. 30, 2024 EUR (€)	Sep. 30, 2016
3.4% Notes [Member]
Derivative [Line Items]
Interest rate on borrowing		3.40%	3.40%	3.40%	3.40%
3.4% Notes [Member] | Fixed Rate Debt [Member]
Derivative [Line Items]
Interest rate on borrowing						3.40%
Net Investment Hedge [Member] | 3.4% Notes [Member] | Cross Currency Swaps [Member]
Derivative [Line Items]
Notional Amount		$ 250,000,000	€ 223,000,000	$ 250,000,000	€ 223,000,000
Net Investment Hedge [Member] | 3.4% Notes [Member] | Fixed Rate Debt [Member] | Cross Currency Swaps [Member]
Derivative [Line Items]
Interest rate on borrowing		3.40%	3.40%	3.40%	3.40%
Not Designated as Hedging Instrument [Member] | Forward Foreign Currency Contracts [Member]
Derivative [Line Items]
Notional Amount	[1]	$ 184,000,000		$ 138,000,000
[1] At September 30, 2025, the Company’s forward foreign exchange contracts were denominated in Euro, Indonesian rupiah, Czech koruna, and Colombian peso.

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- Definition

Derivative notional amount lower buying higher selling of foreign exchange.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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