Income Taxes (Components of the Income Taxes Provision) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Current Tax Provision
Federal	$ 85.6	$ 26.9	$ 163.7
State	28.4	23.8	23.3
Foreign	254.8	262.7	235.5
Total current tax provision	368.8	313.4	422.5
Deferred Tax Provision
Federal	54.7	108.8	9.7
State	(0.1)	(3.6)	2.4
Foreign	39.4	59.8	45.5
Total deferred tax provision	94.0	165.0	57.6
Total income tax provision	$ 462.8	$ 478.4	$ 480.1