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v3.23.1

Investments - Additional Information (Details) $ in Millions |  | 3 Months Ended |
--- | --- | --- | ---
Apr. 05, 2023 USD ($) | Mar. 31, 2023 USD ($) manager Security | Mar. 31, 2022 USD ($) | Dec. 31, 2022 USD ($) Security
Schedule of Investments [Line Items] |  |  |  |
Number of outside managers managing investment portfolio | manager |  | 3 |  |
Accrued investment income |  | $ 76 |  | $ 71
Number of securities with unrealized losses greater than 10% of book value for 12 months or more | Security |  | 482 |  | 567
Total unrealized losses for securities having losses greater than 10% of book value for 12 months or more |  | $ 253 |  | $ 329
Assets held-in-trust |  | 229 |  | 222
Allowance for credit loss |  | (5) | $ (5) |
Disposal Group, Held-for-sale, Not Discontinued Operations | Sound Point Agreement |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Transaction commitment, new and transitioned investments |  | 393 |  |
Subsequent Event | Disposal Group, Held-for-sale, Not Discontinued Operations | Sound Point Agreement |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Transaction commitment, new and transitioned investments | $ 1,000 |  |  |
PCD Accounting Model to PCI Securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Allowance for credit loss |  | 4 | $ 5 |
AGL Subsidiaries |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Assets held-in-trust |  | 1,146 |  | 1,169
Future Equity Investments |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Remaining minimum amount committed |  | 79 |  |
Future Equity Investments | AGL Subsidiaries | AssuredIM managed fixed-maturity securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investments, including distributed gains, authorized amount to invest |  | 853 |  |
Investments, authorized amount to invest |  | 750 |  |
Invested Capital | AGL Subsidiaries | AssuredIM managed fixed-maturity securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Long-term purchase commitment, amount |  | 366 |  |
Unfunded Commitment | AGL Subsidiaries | AssuredIM managed fixed-maturity securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Long-term purchase commitment, amount |  | 247 |  |
Equity in Earnings (Losses) of Investees | AGL Subsidiaries | AssuredIM managed fixed-maturity securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Long-term purchase commitment, amount |  | 613 |  |
Equity in Earnings (Losses) of Investees | AGAS | AssuredIM managed fixed-maturity securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investments, fair value disclosure |  | $ 396 |  | $ 569

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