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v3.23.3

Investments - Additional Information (Details) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 USD ($) Security | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) fund Security manager | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) Security
Schedule of Investments [Line Items] |  |  |  |  |
Number of outside managers managing investment portfolio | manager |  |  | 3 |  |
Funds accounted for as CIVs | fund |  |  | 3 |  |
Total number of investments | fund |  |  | 6 |  |
Accrued investment income | $ 78 |  | $ 78 |  | $ 71
Number of securities with unrealized losses greater than 10% of book value for 12 months or more | Security | 641 |  | 641 |  | 567
Total unrealized losses for securities having losses greater than 10% of book value for 12 months or more | $ 351 |  | $ 351 |  | $ 329
Assets held-in-trust | 224 |  | 224 |  | 222
Allowance for credit loss | (8) | $ (4) | (23) | $ (13) |
Sales | 73 | 207 | 767 | $ 560 |
Securities purchased with credit deterioration | 0 | 22 | 0 |  |
Securities purchased with credit deterioration, amount at par value |  | 31 |  |  |
Allowance for credit loss at acquisition date |  | 2 |  |  |
Discount attributable to other factors |  | $ 7 |  |  |
Disposal Group, Held-for-sale, Not Discontinued Operations | Sound Point Agreement |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Transaction commitment, new and transitioned investments | 1,000 |  |  |  |
AGL Subsidiaries |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Assets held-in-trust | 1,107 |  | 1,107 |  | $ 1,169
Future Equity Investments | Alternative Investment |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Investments, including distributed gains, authorized amount to invest | 132 |  | 132 |  |
Investments, authorized amount to invest | 1,500 |  | 1,500 |  |
Investments, fair value disclosure | 630 |  | 630 |  |
Unfunded committment | 890 |  | 890 |  |
Unfunded committment, committed for specific funds | 332 |  | 332 |  |
Future Equity Investments | AGL Subsidiaries | Alternative Investment |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Investments, authorized amount to invest | 882 |  | 882 |  |
Authorized amount to invest, excluding distributed gains | 750 |  | 750 |  |
Equity in Earnings (Losses) of Investees | AGAS | Alternative Investment |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Investments, fair value disclosure | 469 |  | 469 |  |
Long-term purchase commitment, amount |  |  | 703 |  |
Funded amount | $ 446 |  | $ 446 |  |

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