Derivative Instruments (Non Hedging Derivatives and Embedded Derivatives Effect on Income Statement) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	$ (123)	$ (240)	$ (200)	$ (379)
Gain Loss On Investments Related To Change In Fair Value Of Derivatives Excluding Embedded Derivatives	(93)	(114)	(123)	(204)
Interest credited	(209)	(138)	(424)	(279)
Not Designated as Hedging Instrument
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	(118)	(126)	(95)	(213)
Not Designated as Hedging Instrument \| Interest Rate Swaps
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	(30)	(44)	(10)	(96)
Not Designated as Hedging Instrument \| Financial Futures
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	(10)	23	(19)	28
Not Designated as Hedging Instrument \| Currency Swap [Member]
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	12	11	12	18
Not Designated as Hedging Instrument \| Foreign Currency Forwards
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	(74)	(76)	(93)	(99)
Not Designated as Hedging Instrument \| Consumer Price Index Swap [Member]
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	6	(11)	7	18
Not Designated as Hedging Instrument \| Credit Default Swaps
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	10	(33)	21	(91)
Not Designated as Hedging Instrument \| Equity Options
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	(11)	21	(25)	21
Not Designated as Hedging Instrument \| Embedded Derivatives In Modified Coinsurance Or Funds Withheld Arrangements
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	(20)	(56)	17	(89)
Not Designated as Hedging Instrument \| Embedded Derivatives In Indexed Annuity [Member]
Income Affect Of Non Hedging Derivatives [Line Items]
Interest credited	(5)	(44)	(11)	(80)
Not Designated as Hedging Instrument \| Interest Rate Future
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	2	1	2	3
Not Designated as Hedging Instrument \| Total Return Swap
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	5	0	8	0
Not Designated as Hedging Instrument \| Interest Rate Swaption
Income Affect Of Non Hedging Derivatives [Line Items]
Total investment related gains (losses), net	$ (3)	$ (6)	$ (26)	$ (6)

This item represents the amount recognized in investment related gains (losses) related to the change in the fair value of derivatives, excluding embedded derivatives.

No definition available.

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- Definition

Changes in estimated fair value related to embedded derivatives Abstract.

+ References

No definition available.

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- Definition

Amount of realized and unrealized gain (loss) on investment.

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-Topic 230
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-Name Accounting Standards Codification
-Section 45
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- Definition

Amount of interest expense for allocation to policyholder account balance.

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