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Investments (Net Realized Gains (Losses) And Losses Included In Net Realized Gains (Losses) And Other Comprehensive Income) (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Period Increase (Decrease) |  | $ 34 | $ 91 | $ 172 | $ 169
Debt Securities, Available-for-sale, Gain (Loss), Total |  | (70) | (279) | (357) | (857)
Net realized gains (losses) |  | (103) | (456) | (484) | (936)
Foreign exchange |  | (67) | 202 | (122) | 546
Gain (Loss) on Derivative |  | 54 | (163) | (178) | (1)
Other | [1] | 92 | (40) | 79 | (114)
Huatai Group |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Other |  | 116 |  |  |
Fixed Maturities [Member] |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Debt Securities, Available-for-Sale, Realized Gain (Loss), Excluding Other-than-temporary Impairment |  | 97 | 144 | 116 | 545
Debt Securities, Available-for-Sale, Realized Loss, Excluding Other-than-temporary Impairment |  | (185) | (331) | (457) | (1,158)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Period Increase (Decrease) |  | 34 | (70) | 44 | (133)
Debt Securities, Available-For-Sale, Credit Impairment Charges Intent to Sell | [2] | (16) | (22) | (60) | (111)
Equity Securities |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Equity Securities, FV-NI, Realized Gain (Loss) |  | (100) | (80) | (61) | (287)
Other Investments |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Net realized gains (losses) |  | (1) |  | (1) |
Alternative Investment |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Net realized gains (losses) |  | 40 | (42) | 75 | 17
Other derivative instruments |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Gain (Loss) on Derivative |  | (7) | (19) | (6) | (9)
Investment and embedded derivative instruments |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Gain (Loss) on Derivative |  | $ 9 | $ (198) | $ (92) | $ (232)
[1] | The three and nine months ended September 30, 2023 Includes a one-time realized gain of $116 million as a result of the consolidation of Huatai Group.
[2] | Relates to certain securities we intended to sell and securities written to market entering default.(2)The three and nine months ended September 30, 2023 Includes a one-time realized gain of $116 million as a result of the consolidation of Huatai Group.

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