Financial Instruments (Carrying Amount and Cumulative Hedging Adjustment) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Sep. 30, 2024
Current portion of long-term debt
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Carrying amounts of hedged item	$ 544.4	$ 0.0
Cumulative hedging adjustment, included in carrying amount	(5.2)	0.0
Long-term debt
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Carrying amounts of hedged item	1,502.3	2,057.1
Cumulative hedging adjustment, included in carrying amount	$ (42.3)	$ (36.6)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount of liability hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

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