Share Capital (Outstanding Common Shares) (Details) - shares shares in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Issued and outstanding common shares
Issued common shares (in shares)	628.8	643.8	672.4
Common shares in Share Trusts (in shares)	(0.9)	(1.1)	(1.4)
Outstanding common shares (in shares)	627.9	642.7	671.0

Number of common stock held in a trust that has been set up specifically to accumulate stock for the sole purpose of distribution to participating employees but not yet earned.

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-Name Accounting Standards Codification
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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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-Topic 210
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-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.5-02(29))
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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
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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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- References

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