Investments (Investment Related Gains (Losses) Net) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Abstract]
Other than Temporary Impairment Losses, Investments	$ (6)	$ (11)	$ (20)
Impairment Losses On Debt Securities Available for Sale	(17)	(1)	(1)
Available-for-sale Securities, Realized Losses, Excluding Other than Temporary Impairments	(396)	(65)	(82)
Gain (Loss) on Sale of Equity Investments	(21)	25	(15)
Available-for-sale Securities, Gross Realized Gains	192	299	114
Other Impairment Losses And Change In Mortgage Loan Provision	(16)	29	(38)
Change in fair value of certain limited partnership investments and other, net	38	169	0
Limited partnerships and real estate joint ventures impairment losses	0	0	(18)
Derivatives And Other Investments Net	21	25	24
Gain (Loss) on Sale of Derivatives	(301)	90	3
Realized Investment Gains (Losses)	$ (506)	$ 560	$ (33)

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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Gains (losses) on limited partnerships and real estate joint ventures impairments

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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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-Publisher FASB
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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 realized gain (loss) on investment.

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