Investments (Investment Related Gains (Losses) Net) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Investments [Abstract]
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	$ (9)	$ 7	$ (45)	$ (31)
Gain on investment activity	72	12	172	54
Available-for-sale Securities, Realized Losses, Excluding Other than Temporary Impairments	(113)	(61)	(477)	(173)
Gain (Loss) on Sale of Equity Investments	6	(2)	5	(4)
Other impairment losses and change in mortgage loan provision	(12)	(17)	(20)	(23)
Derivatives and other, net	(14)	7	(2)	24
Total investment related gains (losses), net	(78)	(126)	(498)	(326)
Change In Fair Value Of Certain Limited Partnership Investments And Other, Net	17	25	18	32
Impairment Losses On Debt Securities Available for Sale	0	0	(1)	(1)
Gain (Loss) on Sale of Derivatives	87	(98)	(131)	(222)
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net	(112)	1	(9)	18
Gains (Losses) on Sales of Other Real Estate	$ 0	$ 0	$ (8)	$ 0

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Net realized gains or losses on investments during the period related to the change in value of embedded derivatives and other realized gains and losses not otherwise categorized.

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Impairment Losses On Debt Securities Available for Sale

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Other impairment losses and change in mortgage loan provision.

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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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Amount of realized loss 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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