Consolidated Balance Sheet (Parenthetical) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2023	Sep. 30, 2022
Statement of Financial Position [Abstract]
Accumulated depreciation	$ 1,798.6	$ 1,702.3
Common stock, par value per share (in usd per share)	$ 1.00	$ 1.00
Common stock, shares, issued (in shares)	181.4	181.4
Treasury stock, shares (in shares)	66.5	66.2

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(8)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(14))
-Publisher FASB
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-SubTopic 10
-Section 50
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-Publisher FASB
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Face amount or stated value per share of common stock.

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-Name Accounting Standards Codification
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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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