Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Effective income tax rate	14.40%	14.20%	12.70%	16.60%
U.S. statutory rate	21.00%	21.00%
Income tax liabilities	$ 233.7		$ 233.7		$ 264.8
Gross unrecognized tax benefits	4.3		4.3		4.3
Accrued interest and penalties related to unrecognized tax benefits	1.5		1.5		$ 1.5
Reasonably possible amount of reduction in gross unrecognized tax benefits for the next twelve months	3.8		3.8
Reasonably possible amount of net reduction to income tax provision if unrecognized tax benefits were recognized	$ 5.3		$ 5.3