Income Taxes - Schedule of Income Tax Data (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Components of Income before income taxes
United States	$ 794.2	$ 371.3	$ 885.1
Non-United States	814.3	702.3	641.1
Income before income taxes	1,608.5	1,073.6	1,526.2
Components of Income tax provision
United States	221.3	71.6	149.6
Non-United States	160.6	102.9	190.7
State and local	48.7	13.6	25.7
Total current	430.6	188.1	366.0
Deferred
United States	(84.6)	(10.7)	(154.7)
Non-United States	6.0	(13.0)	(19.0)
State and local	(21.5)	(9.9)	(10.4)
Total deferred	(100.1)	(33.6)	(184.1)
Income tax provision	330.5	154.5	181.9
Total income taxes paid	$ 344.9	$ 340.2	$ 329.3