Employee Retirement Plans - Schedule of Actuarial Assumptions for U.S. Plans (Details) - Pension Benefits	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Weighted-average assumptions:
Discount rate – benefit obligations	5.54%	5.05%	6.09%
Discount rate – benefit cost	5.05%	6.09%	5.70%
Expected return on plan assets	7.50%	7.50%	7.50%
Rate of increase in salary levels	3.25%	3.25%	3.25%