Reportable Segments and Geographic Information - Geographic (Details) - USD ($) $ in Millions	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Geographic Information
Long-Lived Assets	$ 6,682.8	$ 7,486.5	$ 7,543.4
Americas
Geographic Information
Long-Lived Assets	4,473.1	5,357.8	5,379.4
Europe, Middle East, Africa
Geographic Information
Long-Lived Assets	1,797.2	1,759.5	1,781.1
Asia Pacific
Geographic Information
Long-Lived Assets	$ 412.5	$ 369.2	$ 382.9

Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e9038-108599

Name:	us-gaap_NoncurrentAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant