Derivatives - Details of Derivatives Held to Manage Foreign Currency Risk (Detail)		Sep. 30, 2023 USD ($)	Sep. 30, 2023 EUR (€)	Sep. 30, 2022 USD ($)	Sep. 30, 2022 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]	$ 82,000,000		$ 42,000,000

[1] At September 30, 2023, the Company’s forward foreign exchange contracts were denominated in Indonesian rupiah, Czech koruna, and Colombian peso. At September 30, 2022, the Company’s forward foreign exchange contracts were denominated in Indonesian rupiah and Czech koruna.