Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Gain (Loss) on Securities [Line Items]
Investments Impairment	$ (57)	$ (2)	$ (196)	$ (7)
Change in ACL recognized in earnings	(100)	(272)	(255)	(431)
Unrealized net gains (losses) recognized in earnings	(1)	59	(12)	73
Total recognized gains (losses)	(101)	(213)	(267)	(358)
Non-investment portfolio gains (losses)	(32)	87	(155)	151
Net investment gains (losses)	(428)	(273)	(1,098)	(660)
Realized gains (losses) on investments sold or disposed	(238)	(145)	(480)	(446)
Cash Flow Hedging [Member]
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	(22)	4	(30)	6
Realized gains (losses) on investments sold or disposed	(15)	10	(15)	9
Renewable Energy Program
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	$ 20	$ 0
Private Equity Funds
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed			51	2
Equity Method Investment, Amount Sold			745	43
Proceeds from Sale of Equity Method Investments			$ 694	$ 41

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