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, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivatives not designated as hedges, gains (losses) included in net earnings	$ (18)	$ (9)	$ (2)	$ (21)
Earnings (losses) on derivatives	(25)	(8)	(21)	(18)
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	(11)	0	(1)	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)	(4)	(11)
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)	(6)	3	(10)
Designated as hedging instrument \| Interest rate swaps \| Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from accumulated other comprehensive income	$ (7)	$ 1	$ (19)	$ 3

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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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