Derivatives - Gains (losses) included in the Statement of Earnings for changes in the fair value of derivatives (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	$ 5	$ 16	$ 0	$ 9
Earnings (losses) on derivatives	4	14	(2)	4
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Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	(9)	0	(10)	1
Fixed maturities with embedded derivatives \| Income Statement Location [Axis]: us-gaap:NetInvestmentIncome
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	0	7	0	2
Total return swap \| Income Statement Location [Axis]: us-gaap:OtherCostAndExpenseOperating
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	14	9	10	6
Designated as hedging instrument \| Interest rate swaps \| Income Statement Location [Axis]: us-gaap:NetInvestmentIncome
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from accumulated other comprehensive income	$ (1)	$ (2)	$ (2)	$ (5)

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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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