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Fair Value Measurements - Assets and liabilities measured and carried at fair value in the financial statements (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Assets: |  |
Available for sale (AFS) fixed maturities | $ 10,377 | $ 10,095
Trading fixed maturities | 57 | 32
Equity securities, at fair value | 1,018 | 1,010
Assets of managed investment entities | 4,484 | 5,447
Other assets — derivatives | 87 | 40
Total assets accounted for at fair value | 15,942 | 16,584
Liabilities: |  |
Liabilities of managed investment entities | 4,307 | 5,332
Other liabilities — derivatives | 22 | 42
Total liabilities accounted for at fair value | 4,331 | 5,399
Contingent consideration - acquisitions |  |
Liabilities: |  |
Contingent consideration — acquisitions | 2 | 25
Other liabilities — derivatives |  |
Liabilities: |  |
Other liabilities — derivatives | 22 | 42
Fixed maturities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 10,377 | 10,095
Trading fixed maturities | 57 | 32
U.S. Government and government agencies |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 236 | 219
States, municipalities and political subdivisions |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 984 | 1,186
Foreign government |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 230 | 226
Residential MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 1,658 | 1,598
Commercial MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 74 | 85
Collateralized loan obligations |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 1,687 | 1,921
Other asset-backed securities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 2,362 | 2,245
Corporate and other |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 3,146 | 2,615
Equity securities |  |
Assets: |  |
Equity securities, at fair value | 1,018 | 1,010
Other assets |  |
Assets: |  |
Other assets — derivatives | 6 |
Level 1 |  |
Assets: |  |
Assets of managed investment entities | 335 | 659
Total assets accounted for at fair value | 1,079 | 1,442
Liabilities: |  |
Liabilities of managed investment entities | 322 | 645
Total liabilities accounted for at fair value | 322 | 645
Level 1 | Contingent consideration - acquisitions |  |
Liabilities: |  |
Contingent consideration — acquisitions | 0 | 0
Level 1 | Other liabilities — derivatives |  |
Liabilities: |  |
Other liabilities — derivatives | 0 | 0
Level 1 | Fixed maturities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 244 | 227
Trading fixed maturities | 0 | 0
Level 1 | U.S. Government and government agencies |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 235 | 219
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 | Commercial 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 | 9 | 8
Level 1 | Equity securities |  |
Assets: |  |
Equity securities, at fair value | 500 | 556
Level 1 | Other assets |  |
Assets: |  |
Other assets — derivatives | 0 |
Level 2 |  |
Assets: |  |
Assets of managed investment entities | 4,140 | 4,777
Total assets accounted for at fair value | 13,633 | 14,040
Liabilities: |  |
Liabilities of managed investment entities | 3,976 | 4,676
Total liabilities accounted for at fair value | 3,998 | 4,718
Level 2 | Contingent consideration - acquisitions |  |
Liabilities: |  |
Contingent consideration — acquisitions | 0 | 0
Level 2 | Other liabilities — derivatives |  |
Liabilities: |  |
Other liabilities — derivatives | 22 | 42
Level 2 | Fixed maturities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 9,397 | 9,204
Trading fixed maturities | 57 | 32
Level 2 | U.S. Government and government agencies |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 1 | 0
Level 2 | States, municipalities and political subdivisions |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 982 | 1,181
Level 2 | Foreign government |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 230 | 226
Level 2 | Residential MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 1,656 | 1,589
Level 2 | Commercial MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 74 | 85
Level 2 | Collateralized loan obligations |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 1,686 | 1,919
Level 2 | Other asset-backed securities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 2,011 | 1,916
Level 2 | Corporate and other |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 2,757 | 2,288
Level 2 | Equity securities |  |
Assets: |  |
Equity securities, at fair value | 33 | 27
Level 2 | Other assets |  |
Assets: |  |
Other assets — derivatives | 6 |
Level 3 |  |
Assets: |  |
Assets of managed investment entities | 9 | 11
Total assets accounted for at fair value | 1,230 | 1,102
Liabilities: |  |
Liabilities of managed investment entities | 9 | 11
Total liabilities accounted for at fair value | 11 | 36
Level 3 | Contingent consideration - acquisitions |  |
Liabilities: |  |
Contingent consideration — acquisitions | 2 | 25
Level 3 | Other liabilities — derivatives |  |
Liabilities: |  |
Other liabilities — derivatives | 0 | 0
Level 3 | Fixed maturities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 736 | 664
Trading fixed maturities | 0 | 0
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 | 2 | 5
Level 3 | Foreign government |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 3 | Residential MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 2 | 9
Level 3 | Commercial MBS |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 0 | 0
Level 3 | Collateralized loan obligations |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 1 | 2
Level 3 | Other asset-backed securities |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 351 | 329
Level 3 | Corporate and other |  |
Assets: |  |
Available for sale (AFS) fixed maturities | 380 | 319
Level 3 | Equity securities |  |
Assets: |  |
Equity securities, at fair value | 485 | $ 427
Level 3 | Other assets |  |
Assets: |  |
Other assets — derivatives | $ 0 |

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