Intangible Assets, net (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets, Gross	$ 425.9	$ 425.9
Finite-Lived Intangible Assets, Accumulated Amortization	(134.9)	(129.4)
Finite-Lived Intangible Assets, Net	291.0	296.5
Customer Relationships [Member]
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets, Gross	209.4	209.4
Finite-Lived Intangible Assets, Accumulated Amortization	(68.3)	(65.5)
Finite-Lived Intangible Assets, Net	141.1	143.9
Trademarks [Member]
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets, Gross	213.4	213.4
Finite-Lived Intangible Assets, Accumulated Amortization	(63.5)	(60.8)
Finite-Lived Intangible Assets, Net	149.9	152.6
Other Intangible Assets [Member]
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