v3.26.3
Investments - Schedule of Aggregate Fair Value and Gross Unrealized Loss of Fixed Maturity Securities in an Unrealized Loss Position (Details)
$ in Millions
Sep. 30, 2026
USD ($)
security
Dec. 31, 2025
USD ($)
security
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 5,096 1,207
Estimated fair value, less than 12 months $ 20,508 $ 3,594
Gross unrealized loss, less than 12 months $ (1,013) $ (71)
Number of securities, 12 months or greater | security 2,300 2,946
Estimated fair value, 12 months or greater $ 2,772 $ 4,208
Gross unrealized loss, 12 months or greater $ (542) $ (423)
United States Government securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 71 18
Estimated fair value, less than 12 months $ 1,351 $ 460
Gross unrealized loss, less than 12 months $ (76) $ (3)
Number of securities, 12 months or greater | security 13 17
Estimated fair value, 12 months or greater $ 106 $ 167
Gross unrealized loss, 12 months or greater $ (26) $ (16)
Government sponsored securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 12 4
Estimated fair value, less than 12 months $ 24 $ 0
Gross unrealized loss, less than 12 months $ (1) $ 0
Number of securities, 12 months or greater | security 11 16
Estimated fair value, 12 months or greater $ 8 $ 29
Gross unrealized loss, 12 months or greater $ (1) $ (1)
Foreign government securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 5 1
Estimated fair value, less than 12 months $ 14 $ 3
Gross unrealized loss, less than 12 months $ (1) $ 0
Number of securities, 12 months or greater | security 1 2
Estimated fair value, 12 months or greater $ 0 $ 1
Gross unrealized loss, 12 months or greater $ 0 $ 0
States, municipalities and political subdivisions, tax-exempt    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 1,071 213
Estimated fair value, less than 12 months $ 2,729 $ 486
Gross unrealized loss, less than 12 months $ (148) $ (8)
Number of securities, 12 months or greater | security 330 522
Estimated fair value, 12 months or greater $ 510 $ 848
Gross unrealized loss, 12 months or greater $ (89) $ (66)
Corporate securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 2,561 568
Estimated fair value, less than 12 months $ 10,977 $ 1,398
Gross unrealized loss, less than 12 months $ (541) $ (22)
Number of securities, 12 months or greater | security 531 839
Estimated fair value, 12 months or greater $ 752 $ 1,397
Gross unrealized loss, 12 months or greater $ (113) $ (108)
Residential mortgage-backed securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 697 169
Estimated fair value, less than 12 months $ 2,737 $ 282
Gross unrealized loss, less than 12 months $ (152) $ (4)
Number of securities, 12 months or greater | security 1,139 1,164
Estimated fair value, 12 months or greater $ 819 $ 1,012
Gross unrealized loss, 12 months or greater $ (180) $ (132)
Commercial mortgage-backed securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 276 80
Estimated fair value, less than 12 months $ 1,109 $ 308
Gross unrealized loss, less than 12 months $ (41) $ (6)
Number of securities, 12 months or greater | security 110 212
Estimated fair value, 12 months or greater $ 222 $ 479
Gross unrealized loss, 12 months or greater $ (27) $ (25)
Other asset-backed securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 403 154
Estimated fair value, less than 12 months $ 1,567 $ 657
Gross unrealized loss, less than 12 months $ (53) $ (28)
Number of securities, 12 months or greater | security 165 174
Estimated fair value, 12 months or greater $ 355 $ 275
Gross unrealized loss, 12 months or greater $ (106) $ (75)