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)	$ (65)	$ (176)
Equity Securities, FV-NI, Unrealized Gain (Loss)	16	13
Income (Loss) from Equity Method Investments	267	132
Net investment Income
Net Investment Income [Line Items]
Debt and Equity Securities, Realized Gain (Loss)	0	0
Debt and Equity Securities, Unrealized Gain (Loss)	(33)	(14)
Debt and Equity Securities, Gain (Loss)	(33)	(14)
FVO Securities [Member]
Net Investment Income [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ (35)	$ (35)

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

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