Goodwill (Schedule of Goodwill by Segment) (Details) $ in Millions	3 Months Ended
Dec. 31, 2021 USD ($)
Goodwill [Roll Forward]
Goodwill, net, beginning balance	$ 911.5
Acquisitions	17.0
Currency translation and other	(5.2)
Goodwill, net, ending balance	923.3
Americas
Goodwill [Roll Forward]
Goodwill, net, beginning balance	151.0
Acquisitions	0.0
Currency translation and other	(2.3)
Goodwill, net, ending balance	148.7
Asia
Goodwill [Roll Forward]
Goodwill, net, beginning balance	184.3
Acquisitions	0.0
Currency translation and other	0.8
Goodwill, net, ending balance	185.1
Europe
Goodwill [Roll Forward]
Goodwill, net, beginning balance	533.5
Acquisitions	17.0
Currency translation and other	(3.7)
Goodwill, net, ending balance	546.8
Middle East and India
Goodwill [Roll Forward]
Goodwill, net, beginning balance	8.0
Acquisitions	0.0
Currency translation and other	0.0
Goodwill, net, ending balance	8.0
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

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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