The notional amount of contracts closed during the period.

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Represents the percentage of interest sold.

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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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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 amount of remeasurement gain (loss) attributable to reclassification of equity method investment to FVTPL.

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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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The total consideration received from sales of interests in associates.

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The amount of financial assets that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets]

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The gain (loss) recognised as result of remeasuring to fair value the equity interest in the acquiree held by the acquirer before the business combination. [Refer: Total for all business combinations [member]]

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The gains (losses) on disposals of investments.

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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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The gains (losses) recognised in profit or loss for assets measured at fair value that are attributable to the change in unrealised gains or losses relating to those assets held at the end of the reporting period. [Refer: At fair value [member]]

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The cash inflow from sales of investments accounted for using the equity method. [Refer: Investments accounted for using equity method]

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The proportion of ownership interest in an associate attributable to the entity. [Refer: Total for all associates [member]]

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Cash and Investments - Net gains (losses) on investments (Details) $ in Millions, ₨ in Billions				12 Months Ended
	Dec. 20, 2024 USD ($)	Dec. 19, 2024	Nov. 01, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 INR (₨)
Cash and Investments
Net gains (losses) on investments				$ 1,067.2	$ 1,949.5
Common stocks
Cash and Investments
Net realized gains (losses)				507.0	43.9
Net change in unrealized gains (losses)				(210.2)	420.5
Net gains (losses) on investments				296.8	464.4
Bonds and preferred stocks - convertible
Cash and Investments
Net realized gains (losses)				18.2	(0.2)
Net change in unrealized gains (losses)				(3.6)	77.3
Net gains (losses) on investments				14.6	77.1
Other equity derivatives
Cash and Investments
Net realized gains (losses)				375.3	144.0
Net change in unrealized gains (losses)				564.0	213.2
Net gains (losses) on investments				939.3	357.2
Long equity total return swaps on Fairfax subordinate voting shares
Cash and Investments
Net realized gains (losses)				517.7	304.2
Cash-settlement amounts on market value movement				295.3
Cash settlement on closing contracts				222.4
Notional amount of contracts closed during the period				68.5
Disposition of non-insurance associates
Cash and Investments
Net realized gains (losses)				575.5	322.0
Net gains (losses) on investments				575.5	322.0
Other
Cash and Investments
Net realized gains (losses)				32.8	(3.1)
Net gains (losses) on investments				32.8	(3.1)
Long equity exposure and financial effects
Cash and Investments
Net realized gains (losses)				1,508.8	506.6
Net change in unrealized gains (losses)				350.2	711.0
Net gains (losses) on investments				1,859.0	1,217.6
Bonds
Cash and Investments
Net realized gains (losses)				(16.5)	(587.6)
Net change in unrealized gains (losses)				(590.8)	1,141.9
Net gains (losses) on investments				(607.3)	554.3
Fair value				38,235.5	37,441.0
U.S. treasury bond forward contracts
Cash and Investments
Net realized gains (losses)				(90.0)	172.3
Net change in unrealized gains (losses)				(34.0)	(12.5)
Net gains (losses) on investments				(124.0)	159.8
Total bonds
Cash and Investments
Net realized gains (losses)				(106.5)	(415.3)
Net change in unrealized gains (losses)				(624.8)	1,129.4
Net gains (losses) on investments				(731.3)	714.1
Foreign currency
Cash and Investments
Net realized gains (losses)				166.6	(222.5)
Net change in unrealized gains (losses)				(191.8)	103.7
Net gains (losses) on investments				(25.2)	(118.8)
Other
Cash and Investments
Net realized gains (losses)				(17.9)	1.6
Net change in unrealized gains (losses)				(17.4)	135.0
Net gains (losses) on investments				(35.3)	136.6
Net gains (losses) on investments
Cash and Investments
Net realized gains (losses)				1,551.0	(129.6)
Net change in unrealized gains (losses)				(483.8)	2,079.1
Net gains (losses) on investments				1,067.2	1,949.5
Stelco
Cash and Investments
Total consideration received from sale of interests in associates			$ 638.1
Net realized gains (losses) on disposal			$ 343.7
RiverStone Barbados AVLNs \| Long equity total return swaps on Fairfax subordinate voting shares
Cash and Investments
Net change in unrealized gains (losses)				515.8	320.6
Fair value				$ 1,032.7	516.9
Peak Achievement Athletics, Inc.
Cash and Investments
Ownership percentage	100.00%	42.60%
Gain on remeasurement of previously held equity interest	$ 203.4
Fairfax India \| IIFL Finance
Cash and Investments
Net realized gains (losses) on disposal					$ 88.6
Ownership percentage					15.10%	15.10%
Percentage of interest sold					7.10%	7.10%
Proceeds from sale of equity interest					$ 177.3	₨ 14.7
Realized gain on remeasurement of investment					$ 204.2