Investments (Supplemental Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Net Investment Income [Line Items]
Debt and Equity Securities, Realized Gain (Loss)	$ (71)	$ (258)
Equity Securities, FV-NI, Unrealized Gain (Loss)	(9)	10
Income (Loss) from Equity Method Investments	533	267
Net investment income
Net Investment Income [Line Items]
Debt and Equity Securities, Realized Gain (Loss)	171	43
Debt and Equity Securities, Unrealized Gain (Loss)	(549)	(289)
Debt and Equity Securities, Gain (Loss)	(378)	(246)
Unit-linked investments
Net Investment Income [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ (392)	$ (260)

Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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