Receivables - Schedule of Receivables (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Sep. 30, 2020
Receivables [Abstract]
Trade receivables - U.S. government	$ 135.3	$ 140.7	$ 133.5
Trade receivables - other	979.5	797.5	849.2
Finance receivables	7.3	8.0	6.4
Other receivables	53.3	40.0	39.3
Receivables, gross	1,175.4	986.2	1,028.4
Less allowance for doubtful accounts	(6.7)	(4.2)	(3.6)	$ (9.6)
Receivables, net	$ 1,168.7	$ 982.0	$ 1,024.8