CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION (Unaudited) (Parenthetical) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Statement of Financial Position [Abstract]
Property, plant and equipment, accumulated depreciation	$ 419.5	$ 390.8
Capital stock, par value (in dollars per share)	$ 1	$ 1
Capital stock, authorized shares (in shares)	50.0	50.0
Capital stock, shares issued (in shares)	18.1	18.5
Capital stock, shares outstanding (in shares)	18.1	18.5

Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
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-Topic 946
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-Publisher FASB
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- Definition

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.

+ References

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
-Topic 505
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
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-Section S99
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of accumulated depreciation and amortization from plant, property, and equipment and right-of-use asset from finance lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
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-Subparagraph (c)
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-Name Accounting Standards Codification
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- References

No definition available.

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