Other Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Other Income and Expenses [Abstract]
Interest income	$ 1.3	$ 0.5	$ 2.6	$ 1.0
Royalty income	3.4	2.8	5.9	5.5
Legacy product liability and environmental charges	(3.1)	(4.1)	(5.9)	(7.4)
Non-operating pension and postretirement benefit cost	(105.4)	(21.3)	(93.0)	(16.9)
Other	(3.3)	(1.6)	0.6	(3.0)
Other expense	$ (107.1)	$ (23.7)	$ (89.8)	$ (20.8)