Share-Based Compensation (Market-Based Deferred Stock Unit Valuation Assumptions) (Details) - Market-Based Deferred Stock Unit	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	25.00%	32.50%	30.50%
Risk-free interest rate	4.30%	4.00%	0.80%
Expected dividend yield	2.60%	2.40%	2.10%