Intangible Assets (Acquired Intangible Assets) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible assets, gross	$ 673.3	$ 672.3
Accumulated amortization and impairment	(361.7)	(337.7)
Intangible assets, net	311.6	334.6
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	627.1	625.1
Accumulated amortization	(351.8)	(327.6)
Finite-lived intangible assets, net	275.3	297.5
Trade names and trademarks
Acquired Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets, gross	46.2	47.2
Accumulated impairment	(9.9)	(10.1)
Indefinite-lived intangible assets, net	36.3	37.1
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	524.9	507.3
Accumulated amortization	(298.2)	(262.2)
Finite-lived intangible assets, net	226.7	245.1
Patents and technology
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	32.9	41.1
Accumulated amortization	(20.7)	(26.7)
Finite-lived intangible assets, net	12.2	14.4
Other
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	69.3	76.7
Accumulated amortization	(32.9)	(38.7)
Finite-lived intangible assets, net	$ 36.4	$ 38.0