Derivatives and Hedge Accounting - Fair value hedging relationships (Details) - Derivatives designated as hedging instruments - Fair value hedging - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Interest rate contracts \| Income Statement Location [Axis]: us-gaap:InterestCreditedToPolicyholdersAccountBalances
Derivative instruments gain (loss):
Gains/(losses) recognized in earnings on hedging derivatives	$ (66)	$ 56	$ (121)	$ 142
Gains/(losses) recognized in earnings for excluded components	0	0	0	0
Gain (losses) recognized in earnings on hedged items	63	(58)	117	(146)
Net Impact	(3)	(2)	$ (4)	$ (4)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Interest credited to policyholder account balances	Interest credited to policyholder account balances
Interest rate contracts \| Income Statement Location [Axis]: us-gaap:NetInvestmentIncome
Derivative instruments gain (loss):
Gains/(losses) recognized in earnings on hedging derivatives	31	0	$ 42	$ 0
Gains/(losses) recognized in earnings for excluded components	0	0	0	0
Gain (losses) recognized in earnings on hedged items	(31)	0	(42)	0
Net Impact	0	0	$ 0	0
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Interest credited to policyholder account balances, Net investment income:
Foreign exchange contracts
Derivative instruments gain (loss):
Gains/(losses) recognized in earnings on hedging derivatives	33	(619)	$ 210	(883)
Gains/(losses) recognized in earnings for excluded components	(101)	(20)	(18)	127
Gain (losses) recognized in earnings on hedged items	(33)	619	(210)	883
Net Impact	$ (101)	$ (20)	$ (18)	$ 127

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.

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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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