Goodwill (Schedule of Accumulated Impairment Losses) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Sep. 30, 2021
Goodwill [Line Items]
Goodwill, gross	$ 1,250.8	$ 1,239.2
Goodwill, net	912.8	911.5
Americas
Goodwill [Line Items]
Goodwill, accumulated impairment losses	(338.0)	(327.7)
Goodwill, net	$ 152.4	$ 151.0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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