Restructuring and Other Costs - Schedule of Changes in Restructuring Accrual Charges (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Restructuring And Other Costs [Abstract]
Accrual at beginning of fiscal year	$ 55.5	$ 25.2
Additional accruals	22.1	11.6
Payments	(15.0)	(13.7)
Adjustment to accruals	(4.0)	(1.7)
Foreign currency rate changes and other	0.4
Accrual at December 31	$ 59.0	$ 21.4