Intangible Assets, net (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2022	Sep. 30, 2021
Finite-Lived Intangible Assets
Finite-lived intangible assets, gross			$ 376.7	$ 376.8
Finite-lived intangible assets, accumulated amortization			(168.4)	(153.7)
Finite-lived intangible assets, net			208.3	223.1
Accelerated amortization	$ 11.8	$ 29.9
Customer relationships
Finite-Lived Intangible Assets
Finite-lived intangible assets, gross			178.5	178.6
Finite-lived intangible assets, accumulated amortization			(82.6)	(75.3)
Finite-lived intangible assets, net			95.9	103.3
Trademarks and brands
Finite-Lived Intangible Assets
Finite-lived intangible assets, gross			195.1	195.1
Finite-lived intangible assets, accumulated amortization			(82.7)	(75.3)
Finite-lived intangible assets, net			112.4	119.8
Other intangible assets
Finite-Lived Intangible Assets
Finite-lived intangible assets, gross			3.1	3.1
Finite-lived intangible assets, accumulated amortization			(3.1)	(3.1)
Finite-lived intangible assets, net			$ 0.0	$ 0.0