Investments (Investment Related Gains (Losses) Net) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Abstract]
Other than Temporary Impairment Losses, Investments	$ (22)	$ (38)	$ (6)
Impairment Losses On Debt Securities Available for Sale	(1)	(3)	(17)
Available-for-sale Securities, Realized Losses, Excluding Other than Temporary Impairments	(811)	(275)	(396)
Gain (Loss) on Sale of Equity Investments	1	(1)	(21)
Gains (Losses) on Sales of Investment Real Estate	(26)	(16)	(16)
Available-for-sale Securities, Gross Realized Gains	194	72	192
Change in fair value of certain limited partnership investments and other, net	39	48	38
Gain (Loss) On Sale of Free Standing Derivatives	(229)	(129)	(166)
Gain (Loss) on Sale of Derivatives	116	(163)	(173)
Other investment related gains (losses), net	17	24	26
Realized Investment Gains (Losses)	(745)	(481)	(539)
Gains (Losses) on Sales of Other Real Estate	$ (23)	$ 0	$ 0

Change In Fair Value Of Certain Limited Partnership Investments And Other, Net

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Gain (Loss) On Sale of Free Standing Derivatives

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Impairment Losses On Debt Securities Available for Sale

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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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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 real estate owned for investment purposes.

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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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