Goodwill (Schedule of Goodwill by Segment) (Details) $ in Millions	6 Months Ended
Mar. 31, 2022 USD ($)
Goodwill [Roll Forward]
Goodwill, net, beginning balance	$ 911.5
Acquisitions	24.5
Currency translation and other	(23.2)
Goodwill, net, ending balance	912.8
Business combinations, tax deductible goodwill	3.2
Americas
Goodwill [Roll Forward]
Goodwill, net, beginning balance	151.0
Acquisitions	0.0
Currency translation and other	1.4
Goodwill, net, ending balance	152.4
Asia
Goodwill [Roll Forward]
Goodwill, net, beginning balance	184.3
Acquisitions	0.0
Currency translation and other	(0.3)
Goodwill, net, ending balance	184.0
Europe
Goodwill [Roll Forward]
Goodwill, net, beginning balance	533.5
Acquisitions	17.0
Currency translation and other	(24.3)
Goodwill, net, ending balance	526.2
Middle East and India
Goodwill [Roll Forward]
Goodwill, net, beginning balance	8.0
Acquisitions	7.5
Currency translation and other	0.0
Goodwill, net, ending balance	15.5
Corporate and other
Goodwill [Roll Forward]
Goodwill, net, beginning balance	34.7
Acquisitions	0.0
Currency translation and other	0.0
Goodwill, net, ending balance	$ 34.7

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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