Investments (Investment Related Gains (Losses) Net) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Investments [Abstract]
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	$ (20)	$ (42)
Gain on investment activity	32	31
Available-for-sale Securities, Realized Losses, Excluding Other than Temporary Impairments	(134)	(75)
Gain (Loss) on Sale of Equity Investments	4	2
Other impairment losses and change in mortgage loan provision	(10)	3
Gains (Losses) on Sales of Other Real Estate	(8)	0
Derivatives and other, net	(99)	(31)
Total investment related gains (losses), net	(149)	(77)
Change In Fair Value Of Certain Limited Partnership Investments And Other, Net	1	(3)
Impairment Losses On Debt Securities Available for Sale	0	(1)
Gain (Loss) on Sale of Derivatives	77	37
Gain (Loss) on Sale of Other Investments	$ 8	$ 2

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

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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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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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Amount of gain (loss) included in earnings for investments classified as other.

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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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