Derivatives - Gains (losses) included in the Statement of Earnings for changes in the fair value of derivatives (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	$ 11	$ 14	$ 20	$ 20
Earnings (losses) on derivatives	8	8	12	0
Fixed maturities with embedded derivatives \| Securities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	1	3	2	2
Fixed maturities with embedded derivatives \| Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	4	6	6	7
Total return swap \| Other expenses
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	6	5	12	11
Designated as hedging instrument \| Interest rate swaps \| Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from accumulated other comprehensive income	$ (3)	$ (6)	$ (8)	$ (20)

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

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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