Goodwill (Schedule of Accumulated Impairment Losses) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Sep. 30, 2021
Goodwill [Line Items]
Goodwill, gross	$ 1,155.1	$ 1,239.2
Goodwill, net	866.8	911.5
Americas
Goodwill [Line Items]
Goodwill, accumulated impairment losses	(288.3)	(327.7)
Goodwill, net	$ 145.4	$ 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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