Investments (Investment Related Gains (Losses) Net) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Investments [Abstract]
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	$ 30	$ (28)	$ (6)	$ (63)
Gain on investment activity	30	96	125	162
Available-for-sale Securities, Realized Losses, Excluding Other than Temporary Impairments	(132)	(65)	(421)	(217)
Gain (Loss) on Sale of Equity Investments	(8)	5	(25)	7
Other impairment losses and change in mortgage loan provision	(15)	(6)	(25)	(20)
Derivatives and other, net	6	4	12	2
Total investment related gains (losses), net	(85)	13	(331)	(110)
Change In Fair Value Of Certain Limited Partnership Investments And Other, Net	15	9	(21)	8
Impairment Losses On Debt Securities Available for Sale	(45)	(1)	(46)	(3)
Gain (Loss) on Sale of Derivatives	(29)	32	2	80
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net	104	(33)	147	(41)
Other Receivable, Allowance for Credit Loss, Noncurrent	1	1	(2)	(3)
Gains (Losses) on Sales of Other Real Estate	$ (42)	$ (1)	$ (71)	$ (22)

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Other change in allowance for credit losses and impairments

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Amount of increase (decrease) in allowance for credit loss of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

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The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession.

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Amount of realized gain (loss) on investment.

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