Retirement Plans (Schedules of Amounts Recognized in Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Amounts recognized in the Consolidated Balance Sheets
Noncurrent liabilities	$ (57.9)	$ (55.4)
Pension plan
Amounts recognized in the Consolidated Balance Sheets
Noncurrent assets	12.0	0.8
Current liabilities	(0.9)	(0.9)
Noncurrent liabilities	(52.3)	(48.1)
Net amount recognized	(41.2)	(48.2)
Amounts recognized in Accumulated other comprehensive loss
Net loss (gain)	128.6	138.6
Prior service credit	0.0	0.0
Net amount recognized, pre-tax	128.6	138.6
Postretirement plan
Amounts recognized in the Consolidated Balance Sheets
Noncurrent assets	0.0	0.0
Current liabilities	(0.2)	(0.2)
Noncurrent liabilities	(3.9)	(5.3)
Net amount recognized	(4.1)	(5.5)
Amounts recognized in Accumulated other comprehensive loss
Net loss (gain)	(7.4)	(7.4)
Prior service credit	0.0	0.0
Net amount recognized, pre-tax	$ (7.4)	$ (7.4)

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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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