Financial Risk Management - Market Risk - Impact on Net Earnings (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Equity price risk
Financial Risk Management.
Financial asset investments	$ 21,015.2	$ 16,855.0
Equity price risk \| Minimum
Financial Risk Management.
Sensitivity analysis, variation percentage	10.00%	10.00%
Equity price risk \| Maximum
Financial Risk Management.
Sensitivity analysis, variation percentage	20.00%	20.00%
Equity price risk \| 20% increase
Financial Risk Management.
Fair value of equity and equity-related holdings	$ 16,033.0	$ 12,355.7
Hypothetical $ change in net earnings	$ 2,121.0	$ 1,648.7
Hypothetical % change in fair value	19.20%	19.40%
Equity price risk \| 10% increase
Financial Risk Management.
Fair value of equity and equity-related holdings	$ 14,722.2	$ 11,344.2
Hypothetical $ change in net earnings	$ 1,046.6	$ 817.5
Hypothetical % change in fair value	9.50%	9.60%
Equity price risk \| No change
Financial Risk Management.
Fair value of equity and equity-related holdings	$ 13,445.8	$ 10,349.4
Equity price risk \| 10% decrease
Financial Risk Management.
Fair value of equity and equity-related holdings	12,206.0	9,378.4
Hypothetical $ change in net earnings	$ (1,017.5)	$ (798.2)
Hypothetical % change in fair value	(9.20%)	(9.40%)
Equity price risk \| 20% decrease
Financial Risk Management.
Fair value of equity and equity-related holdings	$ 11,011.6	$ 8,431.8
Hypothetical $ change in net earnings	$ (1,998.4)	$ (1,576.4)
Hypothetical % change in fair value	(18.10%)	(18.50%)
Equity price risk \| Ten largest issuers
Financial Risk Management.
Financial asset investments	$ 9,149.9	$ 7,418.2
Risk exposure percentage	12.20%	11.00%
Equity price risk \| Largest single issuer of corporate bonds \| Eurobank
Financial Risk Management.
Financial asset investments	$ 2,728.2	$ 2,374.8
Risk exposure percentage	3.60%	3.50%
Interest rate risk
Financial Risk Management.
Sensitivity analysis, variation percentage	1.00%
Incremental change in interest rate on investments	2.00%

The amount of financial asset investments.

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- Definition

Risk Exposure Associated With Instruments Sharing Characteristic, Concentration Percentage

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- Definition

The percentage change to the fair value of equity and equity-related holdings in a sensitivity analysis.

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- Definition

The increase (decrease) in net earnings as calculated in a sensitivity analysis.

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- Definition

The fair value of equity and equity-related holdings in a sensitivity analysis.

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- Definition

Sensitivity Analysis For Types Of Market Risk, Reasonably Possible Change In Risk Variable, Increment, Percent

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- Definition

Sensitivity Analysis For Types Of Market Risk, Reasonably Possible Change In Risk Variable, Percent

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- Definition

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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