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v3.25.1

Investments - Additional Information (Details) £ in Millions, $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2025 USD ($) security | Mar. 31, 2024 USD ($) | Mar. 31, 2025 GBP (£) security | Dec. 31, 2024 USD ($) security
Schedule of Investments [Line Items] |  |  |  |
Fixed-maturity investments, non-investment grade, percent | 12.30% |  | 12.30% | 12.60%
Estimated Fair Value | $ 6,415 |  |  | $ 6,369
Alternative investment | 892 |  |  |
Accrued investment income | $ 67 |  |  | $ 64
Number of securities with unrealized losses greater than 10% of book value for 12 months or more | security | 371 |  | 371 | 438
Total unrealized losses for securities having losses greater than 10% of book value for 12 months or more | $ 202 |  |  | $ 223
Assets held-in-trust | 82 |  |  | 79
Fixed-maturity securities, trading | 137 |  |  | 147
Securities purchased with credit deterioration | 0 | $ 0 |  |
Insured Financial Obligations, Loss Mitigation Securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Estimated Fair Value | 497 |  |  | 479
Collateralized Loan Obligation Equity Tranches |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Estimated Fair Value | 240 |  |  | 277
Consolidated Investment Vehicles | Alternative Investment |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Equity method investments | 39 |  |  | 33
Contingent Value Instruments |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Fixed-maturity securities, trading | 115 |  |  |
CLOs |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Estimated Fair Value | 542 |  |  | 611
Financial Instrument, Other |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investments, fair value disclosure | 549 |  |  |
Sound Point Capital Management, LP |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Equity method investments | 411 |  |  | 418
AGL Subsidiaries |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Assets held-in-trust | 1,079 |  |  | $ 1,135
Future Equity Investments |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Alternative investment | 892 |  |  |
Investments, authorized amount to invest | 1,500 |  |  |
Future Equity Investments | Alternative Investment |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investments, unfunded commitment | 608 |  |  |
Future Equity Investments | Sound Point Capital Management, LP |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investments, authorized amount to invest | 1,000 |  |  |
Debt Securities Through A Facility |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Purchase commitment, debt securities | $ 142 |  | £ 110 |

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