Derivatives - Gains (losses) included in the Statement of Earnings for changes in the fair value of derivatives (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	$ (7)	$ 5
Earnings (losses) on derivatives	(10)	(2)
Fixed maturities with embedded derivatives \| Realized gains on securities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	1	(1)
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	(5)	0
Total return swap \| Other expenses
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	(3)	6
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)	$ (7)

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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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