Defined Benefit Pension Plan - Reconciliation of Benefit Obligations, Plan Assets, and Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Change in benefit obligation
Beginning balance	$ 16,027	$ 13,847
Interest cost	761	796	$ 794
Benefits paid	(1,063)	(1,003)
Actuarial gain	(1,464)	993
Foreign currency exchange rate changes	64	1,394
Ending balance	14,325	16,027	13,847
Change in plan assets
Beginning balance at fair value	18,382	16,332
Actual return on plan assets	(1,793)	1,131
Benefits paid	(1,063)	(1,003)
Employer's contributions	322	321
Foreign currency exchange rate changes	54	1,601
Ending balance at fair value	15,902	18,382	$ 16,332
Overfunded status of the Scheme	$ 1,577	$ 2,355