The nominal or face amount of derivative instruments closed during the period.

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Notional Amount Per Share

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Number Of Shares Under Equity Swap Contracts

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Number of shares under equity swap contracts that were settled during the period.

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- Definition

The realized gains (losses) on financial assets at fair value through profit or loss.

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No definition available.

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The realized gains (losses) on financial assets at fair value through profit or loss from market value movements.

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No definition available.

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The realized gains (losses) on financial assets at fair value through profit or loss from settlement of closing contracts.

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No definition available.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of financial assets that was included in earnings for the period.

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No definition available.

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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No definition available.

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The gains (losses) on financial assets at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Derivatives - Equity derivative contracts (Details) $ / shares in Units, $ / shares in Units, $ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2024 CAD ($)	Dec. 31, 2025 CAD ($) $ / shares shares	Dec. 31, 2024 CAD ($) $ / shares shares
Derivatives
Net gains (losses) on investments	$ 3,151.4	$ 1,067.2
Long equity total return swaps on individual equities for investment purposes
Derivatives
Notional amount	$ 981.6	$ 981.6
Fairfax subordinate voting shares included in long equity total return swaps
Derivatives
Number of shares under equity swap contracts \| shares	1,760,355	1,760,355		1,760,355	1,760,355
Notional amount	$ 664.0	$ 664.0		$ 846.1	$ 846.1
Notional amount per share \| (per share)	$ 377.19	$ 377.19		$ 480.62	$ 480.62
Fairfax subordinate voting shares
Derivatives
Net gains (losses) on investments	$ 840.6	$ 1,033.5
Realized gains (losses) on financial assets	57.9	517.7
Unrealized gains (losses) on financial assets	782.7	515.8
Realized gains (losses) on financial assets at fair value through profit or loss from market value movements	$ 57.9	295.3
Cash settlement on closing contracts		$ 222.4
Number of shares under derivative contracts closed out \| shares		203,800			203,800
Original notional amount		$ 68.5	$ 88.9