Income Taxes (Schedule of Reconciliation of Income Taxes at Statutory Rate) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Computed tax a federal statutory rate, amount	$ 31.0	$ 25.8	$ 30.7
State income taxes, net of federal tax benefit, amount	2.7	2.7	0.8
Foreign tax less than the federal rate, amount	(1.0)	(11.7)	(9.0)
Adjustments to prior years' tax accruals	(6.1)	1.6	(4.3)
Other taxes including repatriation of foreign earnings, amount	4.4	4.6	8.9
Other adjustments, amount	1.4	3.9	2.7
Uncertain tax position	0.6	(2.3)	(0.5)
Income tax provision (benefit)	$ 33.0	$ 24.6	$ 29.3
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Computed tax at federal statutory rate, percent	21.00%	21.00%	21.00%
State income taxes, net of federal tax benefit, percent	1.80%	2.20%	0.60%
Foreign tax less than the federal rate, perecent	(0.70%)	(9.50%)	(6.20%)
Adjustments to prior years' tax accruals, percent	(4.20%)	1.30%	(2.90%)
Other taxes including repatriation of foreign earnings, percent	3.10%	3.70%	6.10%
Other, net, percent	0.90%	3.20%	1.80%
Uncertain tax position, percent	0.40%	(2.00%)	(0.60%)
Total, percent	22.30%	19.90%	19.80%