Retirement Benefits (Assumptions in Calculating Projected Benefit Obligation) (Details) - Defined Benefit Pension Plan	Sep. 30, 2025	Sep. 30, 2024
U.S.
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.20%	5.00%
Rate of compensation increase	3.50%	3.50%
International
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.20%	4.60%
Rate of compensation increase	3.40%	3.40%