Other (Expense) Income (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Components of other income (expense)
Interest income	$ 5.5	$ 11.1	$ 24.4
Royalty income	8.9	10.2	9.7
Legacy product liability and environmental (charges) benefit	(14.5)	(22.1)	2.6
Non-operating pension and postretirement benefit (cost) credit	(37.4)	8.4	(23.8)
Other	7.8	(1.5)	3.9
Other (expense) income	$ (29.7)	$ 6.1	$ 16.8

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.

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No definition available.

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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.

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No definition available.

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- Definition

Other income expense.

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No definition available.

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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.

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No definition available.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(b))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

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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.

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