Derivatives and Hedge Accounting - Fair value hedging relationships (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Interest credited to policyholder account balances
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	Interest credited to policyholder account balances	Interest credited to policyholder account balances
Net Investment Income
Derivative instruments gain (loss):
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Net Investment Income	Net Investment Income	Net Investment Income	Net Investment Income
Derivatives designated as hedging instruments \| Fair value hedging \| Interest rate contracts
Derivative instruments gain (loss):
Gains/(losses) recognized in earnings on hedging derivatives	$ (48)		$ (12)
Gains/(losses) recognized in earnings for excluded components	0		1
Gains/(losses) recognized in earnings for hedged items	53		3
Net Impact	5		(8)
Derivatives designated as hedging instruments \| Fair value hedging \| Interest rate contracts \| Interest credited to policyholder account balances
Derivative instruments gain (loss):
Gains/(losses) recognized in earnings on hedging derivatives		$ (62)		$ (90)
Gains/(losses) recognized in earnings for excluded components		0		0
Gains/(losses) recognized in earnings for hedged items		62		93
Net Impact		0		3
Derivatives designated as hedging instruments \| Fair value hedging \| Interest rate contracts \| Net Investment Income
Derivative instruments gain (loss):
Gains/(losses) recognized in earnings on hedging derivatives		25		26
Gains/(losses) recognized in earnings for excluded components		0		0
Gains/(losses) recognized in earnings for hedged items		(24)		(25)
Net Impact		1		1
Derivatives designated as hedging instruments \| Fair value hedging \| Foreign exchange contracts
Derivative instruments gain (loss):
Gains/(losses) recognized in earnings on hedging derivatives	231	455	(213)	889
Gains/(losses) recognized in earnings for excluded components	(129)	122	68	262
Gains/(losses) recognized in earnings for hedged items	(231)	(455)	213	(889)
Net Impact	$ (129)	$ 122	$ 68	$ 262

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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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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