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Fair Value Measurements - Assets and liabilities measured and carried at fair value in the financial statements (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Assets: |  |
Available for sale (AFS) fixed maturities | $ 10,518 | $ 10,398
Trading fixed maturities | 80 | 76
Equity securities | 800 | 751
Assets of managed investment entities | 3,972 | 4,140
Other assets | 55 | 82
Total assets accounted for at fair value | 15,374 | 15,366
Liabilities: |  |
Liabilities of managed investment entities | 3,834 | 3,965
Derivative liability | 5 | 18
Total liabilities accounted for at fair value | 3,840 | 3,985
Contingent consideration — acquisitions |  |
Liabilities: |  |
Fair value of potential contingent consideration | 1 | 2
Other liabilities — derivatives |  |
Liabilities: |  |
Derivative liability | 5 | 18
Fixed maturities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 10,518 | 10,398
Trading fixed maturities | 80 | 76
U.S. government and government agencies |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 170 | 173
States, municipalities and political subdivisions |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 853 | 859
Foreign government |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 253 | 237
Residential MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 2,311 | 1,989
Collateralized loan obligations |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 1,100 | 1,237
Other asset-backed securities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 2,403 | 2,407
Corporate and other |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 3,428 | 3,496
Equity securities |  |
Assets: |  |
Equity securities | 800 | 751
Other assets |  |
Assets: |  |
Other assets | 4 | 1
Level 1 |  |
Assets: |  |
Assets of managed investment entities | 269 | 419
Total assets accounted for at fair value | 896 | 1,023
Liabilities: |  |
Liabilities of managed investment entities | 260 | 402
Total liabilities accounted for at fair value | 260 | 402
Level 1 | Contingent consideration — acquisitions |  |
Liabilities: |  |
Fair value of potential contingent consideration | 0 | 0
Level 1 | Other liabilities — derivatives |  |
Liabilities: |  |
Derivative liability | 0 | 0
Level 1 | Fixed maturities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 168 | 185
Trading fixed maturities | 0 | 0
Level 1 | U.S. government and government agencies |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 167 | 173
Level 1 | States, municipalities and political subdivisions |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 1 | Foreign government |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 1 | Residential MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 1 | Collateralized loan obligations |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 1 | Other asset-backed securities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 1 | Corporate and other |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 1 | 12
Level 1 | Equity securities |  |
Assets: |  |
Equity securities | 459 | 419
Level 1 | Other assets |  |
Assets: |  |
Other assets | 0 | 0
Level 2 |  |
Assets: |  |
Assets of managed investment entities | 3,689 | 3,711
Total assets accounted for at fair value | 13,474 | 13,247
Liabilities: |  |
Liabilities of managed investment entities | 3,561 | 3,553
Total liabilities accounted for at fair value | 3,566 | 3,571
Level 2 | Contingent consideration — acquisitions |  |
Liabilities: |  |
Fair value of potential contingent consideration | 0 | 0
Level 2 | Other liabilities — derivatives |  |
Liabilities: |  |
Derivative liability | 5 | 18
Level 2 | Fixed maturities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 9,665 | 9,445
Trading fixed maturities | 66 | 50
Level 2 | U.S. government and government agencies |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 3 | 0
Level 2 | States, municipalities and political subdivisions |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 848 | 858
Level 2 | Foreign government |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 253 | 237
Level 2 | Residential MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 2,308 | 1,988
Level 2 | Collateralized loan obligations |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 1,100 | 1,237
Level 2 | Other asset-backed securities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 2,126 | 2,111
Level 2 | Corporate and other |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 3,027 | 3,014
Level 2 | Equity securities |  |
Assets: |  |
Equity securities | 50 | 40
Level 2 | Other assets |  |
Assets: |  |
Other assets | 4 | 1
Level 3 |  |
Assets: |  |
Assets of managed investment entities | 14 | 10
Total assets accounted for at fair value | 1,004 | 1,096
Liabilities: |  |
Liabilities of managed investment entities | 13 | 10
Total liabilities accounted for at fair value | 14 | 12
Level 3 | Contingent consideration — acquisitions |  |
Liabilities: |  |
Fair value of potential contingent consideration | 1 | 2
Level 3 | Other liabilities — derivatives |  |
Liabilities: |  |
Derivative liability | 0 | 0
Level 3 | Fixed maturities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 685 | 768
Trading fixed maturities | 14 | 26
Level 3 | U.S. government and government agencies |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 3 | States, municipalities and political subdivisions |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 5 | 1
Level 3 | Foreign government |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 3 | Residential MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 3 | 1
Level 3 | Collateralized loan obligations |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 3 | Other asset-backed securities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 277 | 296
Level 3 | Corporate and other |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 400 | 470
Level 3 | Equity securities |  |
Assets: |  |
Equity securities | 291 | 292
Level 3 | Other assets |  |
Assets: |  |
Other assets | $ 0 | $ 0

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