Total Equity - Net Changes In Capitalization (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
As presented in other net changes in capitalization in the consolidated statement of changes in equity	$ (65.2)	$ (555.5)
Common shareholders' equity
Other	(67.5)	(75.8)
As presented in other net changes in capitalization in the consolidated statement of changes in equity	123.9	(42.0)
Common shareholders' equity \| Series E, F, G, H, I, J and M
Redemption of cumulative preferred shares	187.1
Common shareholders' equity \| Series C and D
Redemption of cumulative preferred shares		53.5
Non-controlling interests
Other	(41.4)	21.9
As presented in other net changes in capitalization in the consolidated statement of changes in equity	(189.1)	(513.5)
Recipe \| Common shareholders' equity
Share repurchases and cancellation	4.3
Recipe \| Non-controlling interests
Share repurchases and cancellation	$ (147.7)
Brit \| Common shareholders' equity
Acquisition of non-controlling interests		(76.0)
Brit \| Non-controlling interests
Acquisition of non-controlling interests		(449.9)
Gulf Insurance \| Common shareholders' equity
Additional interest acquired in Gulf Insurance through mandatory tender offer		(41.2)
Gulf Insurance \| Non-controlling interests
Additional interest acquired in Gulf Insurance through mandatory tender offer		(85.5)
Digit \| Common shareholders' equity
Partial disposition of Digit Insurance by Digit on completion of Digit Insurance's initial public offering (note 6)		$ 97.5

Amount of decrease in equity from acquisition of a portion of non-controlling interest.

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- Definition

The amount of gain (loss) on redemption of preferred shares recognized in the statement of equity during the reporting period.

+ References

No definition available.

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- Definition

The amount of increase (decrease) in equity related to net changes in capitalization during the period.

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No definition available.

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- Definition

The increase (decrease) in the equity resulting from the partial disposition of shares in the subsidiary of the entity's associate during the reporting period.

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No definition available.

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- Definition

Increase (Decrease) Through Other, Equity

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No definition available.

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- Definition

The increase (decrease) in equity through changes in ownership interests in subsidiaries that do not result in loss of control. [Refer: Total for all subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
-Name IAS
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-IssueDate 2025-01-01
-Paragraph 106
-Subparagraph d
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- Definition

The increase (decrease) in equity resulting from treasury share transactions. [Refer: Equity; Treasury shares]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
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