Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Income tax expense	$ 9.0	$ 15.4	$ 16.1	$ 28.4
Effective Income Tax Rate Reconciliation, Percent	25.10%	24.40%	25.20%	24.30%
Deferred Income Tax Liabilities, Net of Deferred Income Tax Assets	$ (34.8)		$ (34.8)		$ (35.9)
Deferred Tax Assets, Valuation Allowance	0.9		0.9		1.0
Deferred tax liability, net	$ (35.7)		$ (35.7)		$ (36.9)