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v3.26.1

Investments - Additional Information (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2026 USD ($) security | Mar. 31, 2025 USD ($) | Dec. 31, 2025 USD ($) security
Schedule of Investments [Line Items] |  |  |
Fixed-maturity investments, non-investment grade, percent | 7.00% |  | 8.60%
Fixed-maturity securities, available for sale | $ 6,875 |  | $ 6,369
Alternative investment | 965 |  |
Accrued investment income | $ 77 |  | $ 70
Number of securities with unrealized losses greater than 10% of book value for 12 months or more | security | 270 |  | 253
Total unrealized losses for securities having losses greater than 10% of book value for 12 months or more | $ 152 |  | $ 147
Assets held-in-trust | 76 |  | 77
Fixed-maturity securities, trading | 127 |  | 124
Securities purchased with credit deterioration | 0 | $ 0 |
Asset Pledged as Collateral |  |  |
Schedule of Investments [Line Items] |  |  |
Fixed-maturity securities, available for sale | 4 |  |
Insured Financial Obligations, Loss Mitigation Securities |  |  |
Schedule of Investments [Line Items] |  |  |
Fixed-maturity securities, available for sale | 135 |  | 140
Collateralized Loan Obligation Equity Tranches |  |  |
Schedule of Investments [Line Items] |  |  |
Fixed-maturity securities, available for sale | 173 |  | 228
Contingent Value Instruments |  |  |
Schedule of Investments [Line Items] |  |  |
Fixed-maturity securities, trading | 119 |  | 114
Financial Instrument, Other |  |  |
Schedule of Investments [Line Items] |  |  |
Investments, fair value disclosure | 730 |  |
Liquidity Bonds |  |  |
Schedule of Investments [Line Items] |  |  |
Fixed-maturity securities, available for sale | 162 |  | 168
AGL Subsidiaries |  |  |
Schedule of Investments [Line Items] |  |  |
Assets held-in-trust | 812 |  | $ 813
Future Equity Investments |  |  |
Schedule of Investments [Line Items] |  |  |
Alternative investment | 965 |  |
Investments, unfunded commitment | 554 |  |
Alternative Investments, Authorized Amount To Invest | 1,500 |  |
Future Equity Investments | Sound Point Capital Management, LP |  |  |
Schedule of Investments [Line Items] |  |  |
Investments, authorized amount to invest | $ 1,000 |  |

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