Other Income (Expense) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Other Income and Expenses [Abstract]
Interest income	$ 0.6	$ 0.3	$ 1.6	$ 1.1
Royalty income	3.1	2.9	8.6	7.5
Legacy product liability and environmental benefit (charges)	0.8	(4.0)	(6.6)	(9.4)
Non-operating pension and postretirement benefit credit (cost)	11.9	(34.3)	(5.0)	(48.3)
Legal settlement	0.0	0.0	0.0	70.0
Other	3.4	0.2	0.4	(0.8)
Other income (expense)	$ 19.8	$ (34.9)	$ (1.0)	$ 20.1