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Related Party Disclosures (Reinsurance Details) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Related Party Transaction [Line Items]
Other Income	$ 852	$ 687
Premiums, reinsurance and other receivables relating to variable interest entities	50,335		$ 49,059
Net derivative gains (losses)	74	432
Reinsurance Agreement [Member]
Related Party Transaction [Line Items]
Other Income	39
Net derivative gains (losses)	106
Other segment expenses (2)	92
Corporate And Other \| Reinsurance Agreement [Member]
Related Party Transaction [Line Items]
Surrenders and withdrawals	(74)
Life and Other \| Corporate And Other
Related Party Transaction [Line Items]
Surrenders and withdrawals	(74)	$ (56)
Chariot Re [Member] \| Reinsurance Agreement [Member]
Related Party Transaction [Line Items]
Premiums, reinsurance and other receivables relating to variable interest entities	10,200		9,800
Funds Held under Reinsurance Agreements, Liability	$ 10,600		$ 10,500