Schedule II: Valuation and Qualifying Accounts (Details) - SEC Schedule, 12-09, Allowance, Credit Loss - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Changes in valuation and qualifying accounts
Balance at Beginning of Year	$ 94.2	$ 104.0	$ 92.8
Additions Charged to Cost of Revenue	30.9	40.9	43.9
Deductions	(38.7)	(50.8)	(29.6)
Other and Foreign Exchange Impact	1.5	0.1	(3.1)
Balance at the End of the Year	$ 87.9	$ 94.2	$ 104.0

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

No definition available.

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- Definition

Amount of increase (decrease) in valuation and qualifying accounts and reserves from adjustment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-4

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Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column B))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column E))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-4

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Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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Amount of decrease in valuation and qualifying accounts and reserves.

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