Derivative Financial Instruments - Summary of (Loss) Income Related to Foreign Forward Currency Contracts (Details) - Foreign Exchange Forward Contracts - Not Designated - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Derivative Instruments Gain Loss [Line Items]
(Loss) income recognized in earnings	$ (2,492)	$ 860	$ 2,512
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)