v3.26.3
Fair Value Measurements - Assets and liabilities measured and carried at fair value in the financial statements (Details) - USD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
Assets:    
Available for sale (AFS) fixed maturities $ 11,771 $ 11,052
Trading fixed maturities 75 91
Equity securities, at fair value 765 785
Assets of managed investment entities 4,556 4,050
Other assets 1,402 1,280
Total assets accounted for at fair value 17,167 15,979
Liabilities:    
Liabilities of managed investment entities 4,401 3,907
Other liabilities - derivatives 2,446 2,070
Total liabilities accounted for at fair value 4,434 3,913
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilities    
Liabilities:    
Contingent consideration — acquisitions 3 3
Other liabilities — derivatives    
Liabilities:    
Other liabilities - derivatives 30 3
Fixed maturities    
Assets:    
Available for sale (AFS) fixed maturities 11,771 11,052
Trading fixed maturities 75 91
U.S. government and government agencies    
Assets:    
Available for sale (AFS) fixed maturities 132 161
States, municipalities and political subdivisions    
Assets:    
Available for sale (AFS) fixed maturities 698 835
Foreign government    
Assets:    
Available for sale (AFS) fixed maturities 228 238
Residential MBS    
Assets:    
Available for sale (AFS) fixed maturities 3,457 2,747
Collateralized loan obligations    
Assets:    
Available for sale (AFS) fixed maturities 1,237 1,160
Other asset-backed securities    
Assets:    
Available for sale (AFS) fixed maturities 2,672 2,525
Corporate and other    
Assets:    
Available for sale (AFS) fixed maturities 3,347 3,386
Equity securities    
Assets:    
Equity securities, at fair value 765 785
Other assets — derivatives    
Assets:    
Other assets   1
Level 1    
Assets:    
Assets of managed investment entities 343 310
Total assets accounted for at fair value 929 946
Liabilities:    
Liabilities of managed investment entities 332 298
Total liabilities accounted for at fair value 332 298
Level 1 | Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilities    
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 130 158
Trading fixed maturities 0 0
Level 1 | U.S. government and government agencies    
Assets:    
Available for sale (AFS) fixed maturities 129 157
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 1
Level 1 | Equity securities    
Assets:    
Equity securities, at fair value 456 478
Level 1 | Other assets — derivatives    
Assets:    
Other assets   0
Level 2    
Assets:    
Assets of managed investment entities 4,197 3,725
Total assets accounted for at fair value 15,241 14,025
Liabilities:    
Liabilities of managed investment entities 4,054 3,594
Total liabilities accounted for at fair value 4,084 3,597
Level 2 | Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilities    
Liabilities:    
Contingent consideration — acquisitions 0 0
Level 2 | Other liabilities — derivatives    
Liabilities:    
Other liabilities - derivatives 30 3
Level 2 | Fixed maturities    
Assets:    
Available for sale (AFS) fixed maturities 10,918 10,182
Trading fixed maturities 66 66
Level 2 | U.S. government and government agencies    
Assets:    
Available for sale (AFS) fixed maturities 3 4
Level 2 | States, municipalities and political subdivisions    
Assets:    
Available for sale (AFS) fixed maturities 693 831
Level 2 | Foreign government    
Assets:    
Available for sale (AFS) fixed maturities 228 238
Level 2 | Residential MBS    
Assets:    
Available for sale (AFS) fixed maturities 3,455 2,744
Level 2 | Collateralized loan obligations    
Assets:    
Available for sale (AFS) fixed maturities 1,237 1,160
Level 2 | Other asset-backed securities    
Assets:    
Available for sale (AFS) fixed maturities 2,317 2,215
Level 2 | Corporate and other    
Assets:    
Available for sale (AFS) fixed maturities 2,985 2,990
Level 2 | Equity securities    
Assets:    
Equity securities, at fair value 60 51
Level 2 | Other assets — derivatives    
Assets:    
Other assets   1
Level 3    
Assets:    
Assets of managed investment entities 16 15
Total assets accounted for at fair value 997 1,008
Liabilities:    
Liabilities of managed investment entities 15 15
Total liabilities accounted for at fair value 18 18
Level 3 | Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilities    
Liabilities:    
Contingent consideration — acquisitions 3 3
Level 3 | Other liabilities — derivatives    
Liabilities:    
Other liabilities - derivatives 0 0
Level 3 | Fixed maturities    
Assets:    
Available for sale (AFS) fixed maturities 723 712
Trading fixed maturities 9 25
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 4
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 3
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 355 310
Level 3 | Corporate and other    
Assets:    
Available for sale (AFS) fixed maturities 361 395
Level 3 | Equity securities    
Assets:    
Equity securities, at fair value $ 249 256
Level 3 | Other assets — derivatives    
Assets:    
Other assets   $ 0