Derivatives and Hedge Accounting - Fair value hedging relationships (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Derivative instruments gain (loss):
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest credited to policyholder account balances	Interest credited to policyholder account balances
Derivatives designated as hedging instruments \| Fair value hedging \| Interest rate contracts
Derivative instruments gain (loss):
Gains/(losses) recognized in earnings on hedging derivatives	$ (59)	$ 86
Gains/(losses) recognized in earnings for excluded components	0	0
Gain (losses) recognized in earnings on hedged items	65	(88)
Net Impact	6	(2)
Derivatives designated as hedging instruments \| Fair value hedging \| Foreign exchange contracts
Derivative instruments gain (loss):
Gains/(losses) recognized in earnings on hedging derivatives	144	(83)
Gains/(losses) recognized in earnings for excluded components	(11)	79
Gain (losses) recognized in earnings on hedged items	(144)	83
Net Impact	$ (11)	$ 79

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

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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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Net gain (loss) relating to components of the gain (loss) on the fair value hedging instrument excluded from the assessment of fair value hedge effectiveness. Recognized in earnings.

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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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