Other Income (Expense) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Components of other income (expense)
Interest income	$ 15.6	$ 9.7	$ 4.4
Royalty income	11.3	13.2	10.9
Legacy product liability and environmental charges	(20.5)	(18.1)	(15.6)
Non-operating pension and postretirement benefit credit (cost)	19.8	(82.7)	(4.7)
Fair value adjustments for earnout payments (Note 4)	30.7	0.0	0.0
Other	5.9	6.6	3.4
Other income (expense)	$ 62.8	$ (71.3)	$ (1.6)

Legacy product liability and environmental charges.

No definition available.

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- Definition

Non-operating pension costs consist of defined benefit plan interest cost, expected return on plan assets, amortization of actuarial gains and losses and the impacts of any plan curtailments or settlements. These costs are excluded from segment operating earnings.

+ References

No definition available.

+ Details

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- Definition

The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business). Such amounts include: (a) Net (loss) gain on dispositions of securities and property, (b) interest income, (c) royalty income, (d) environmental charges, (e) gains or losses on deferred compensation plans, and (f) miscellaneous other income and expense items.

+ References

No definition available.

+ Details

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- Definition

Other income expense.

+ References

No definition available.

+ Details

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- Definition

The net amount of other income and expense, which does not qualify for separate disclosure in the footnotes to the financial statements.

+ References

No definition available.

+ Details

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
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-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7)(b))
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(6))
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

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- Definition

Ancillary revenue earned during the period from the consideration paid to the entity for the use of its rights and property by another party. Examples include licensing the use of copyrighted materials and leasing the extraction of natural resources.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7))
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