Investments (Investment Related Gains (Losses) Net) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Investments [Abstract]
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	$ 7	$ 3	$ (31)	$ (21)
Gain on investment activity	12	20	54	65
Available-for-sale Securities, Realized Losses, Excluding Other than Temporary Impairments	(61)	(106)	(173)	(236)
Gain (Loss) on Sale of Equity Investments	(2)	7	(4)	(16)
Other impairment losses and change in mortgage loan provision	(17)	(5)	(23)	(8)
Derivatives and other, net	7	7	24	26
Total investment related gains (losses), net	(126)	(154)	(326)	(533)
Change In Fair Value Of Certain Limited Partnership Investments And Other, Net	25	0	32	29
Impairment Losses On Debt Securities Available for Sale	0	(12)	(1)	(15)
Gain (Loss) on Sale of Derivatives	(98)	(51)	(222)	(251)
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net	$ 1	$ (17)	$ 18	$ (106)

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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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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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Amount of realized gain (loss) on investment.

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