Derivative Financial Instruments - Schedule of Notional Amounts of Outstanding Forward Contracts (Details) - Forward Contracts - USD ($) $ in Thousands	Mar. 31, 2026	Sep. 30, 2025
Designated as Hedging Instrument | Net Investment Hedging
Derivative [Line Items]
Notional amount	$ 535,811	$ 490,458
Euro / U.S. Dollar
Derivative [Line Items]
Notional amount	677,500	835,400
Euro / U.S. Dollar | Designated as Hedging Instrument | Net Investment Hedging
Derivative [Line Items]
Notional amount	516,854	480,198
Japanese Yen / U.S. Dollar
Derivative [Line Items]
Notional amount	40,400	41,900
Japanese Yen / U.S. Dollar | Designated as Hedging Instrument | Net Investment Hedging
Derivative [Line Items]
Notional amount	$ 18,957	$ 10,260