v3.26.3
Investments - (Narrative) (Details)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
USD ($)
security
Sep. 30, 2025
USD ($)
Sep. 30, 2026
USD ($)
security
Sep. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
security
Investments [Abstract]          
Equity Securities at Fair Value $ 13,145   $ 13,145   $ 12,694
Fair value of largest single common stock holding $ 1,156   $ 1,156   $ 958
Largest equity holdings to total equity portfolio 9.00%   9.00%   7.70%
Largest equity holdings to total investment portfolio 3.60%   3.60%   3.10%
Allowance for credit loss on fixed-maturity $ 59   $ 59   $ 54
Reductions in the allowance for credit losses for securities sold $ 1 $ 6 $ 2 $ 7  
Number of fixed-maturity securities in a total unrealized loss position | security 5,241   5,241   2,597
Investments, Available-for-Sale, Accumulated Gross Unrealized Loss Before Tax $ 1,516   $ 1,516   $ 397
Number of fixed-maturity securities in continuous unrealized loss position and below 70 percent of amortized cost 113   113   13
Fixed maturity investments, Percentage of amortized costs 70.00%   70.00%   70.00%