Retirement Plans (Schedule of Actuarial Assumptions) (Details)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Pension plan
Plan obligations:
Discount rate	5.10%	2.30%	2.10%
Compensation increase rate	2.50%	2.50%	2.50%
Net periodic benefit cost:
Discount rate	2.30%	2.10%	2.50%
Expected long-term rate of return on plan assets	4.20%	4.50%	4.80%
Compensation increase rate	2.50%	2.50%	2.50%
Cash balance interest credit rate	3.30%	1.90%	1.30%
Postretirement plan
Plan obligations:
Discount rate	5.10%	3.50%	2.80%
Net periodic benefit cost:
Discount rate	3.50%	2.80%	3.00%
Compensation increase rate	4.00%