v3.26.1
Investments (Details) - Investment Information, Debt Securities - USD ($)
$ in Millions
 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Mar. 31, 2026
Dec. 31, 2025
Mar. 31, 2025
Dec. 31, 2024
Investment disclosure details            
Fixed maturities, amortized cost $ 95,401     $ 91,717    
Allowance for expected credit losses 2     3    
Gross unrealized gains 600     968    
Gross unrealized losses 3,077     2,849    
Fixed maturities, at fair value 92,922     89,833    
Proceeds from sales of fixed maturities classified as available for sale 385 $ 601        
Gross realized gains 1 3        
Gross realized losses on sales of fixed maturities 30 26        
Realized losses resulting from the early redemption of fixed maturities by the issuer prior to the bonds' maturity date 14 23        
Amounts classified as held for sale [Member]            
Investment disclosure details            
Fixed maturities, amortized cost       3,221    
Fixed maturities, at fair value       3,243    
U.S. Treasury securities and obligations of U.S. government and government agencies and authorities [Member]            
Investment disclosure details            
Fixed maturities, amortized cost 3,380     3,927    
Allowance for expected credit losses 0     0    
Gross unrealized gains 1     11    
Gross unrealized losses 100     81    
Fixed maturities, at fair value 3,281     3,857    
Obligations of U.S. states, municipalities and political subdivisions [Member]            
Investment disclosure details            
Fixed maturities, amortized cost 34,427     32,819    
Allowance for expected credit losses 0     0    
Gross unrealized gains 268     229    
Gross unrealized losses 1,638     1,670    
Fixed maturities, at fair value 33,057     31,378    
Obligations of U.S. states, municipalities and political subdivisions, local general obligation [Member]            
Investment disclosure details            
Fixed maturities, amortized cost 22,923     21,724    
Allowance for expected credit losses 0     0    
Gross unrealized gains 182     161    
Gross unrealized losses 1,095     1,096    
Fixed maturities, at fair value 22,010     20,789    
Obligations of U.S. states, municipalities and political subdivisions, revenue [Member]            
Investment disclosure details            
Fixed maturities, amortized cost 10,252     9,810    
Allowance for expected credit losses 0     0    
Gross unrealized gains 79     58    
Gross unrealized losses 515     543    
Fixed maturities, at fair value 9,816     9,325    
Obligations of U.S. states, municipalities and political subdivisions, state general obligation [Member]            
Investment disclosure details            
Fixed maturities, amortized cost 808     871    
Allowance for expected credit losses 0     0    
Gross unrealized gains 5     6    
Gross unrealized losses 25     29    
Fixed maturities, at fair value 788     848    
Obligations of U.S. states, municipalities and political subdivisions, pre-refunded [Member]            
Investment disclosure details            
Fixed maturities, amortized cost 444     414    
Allowance for expected credit losses 0     0    
Gross unrealized gains 2     4    
Gross unrealized losses 3     2    
Fixed maturities, at fair value 443     416    
Debt securities issued by foreign governments [Member]            
Investment disclosure details            
Fixed maturities, amortized cost 399     313    
Allowance for expected credit losses 0     0    
Gross unrealized gains 1     2    
Gross unrealized losses 3     3    
Fixed maturities, at fair value 397     312    
Mortgage-backed securities, collateralized mortgage obligations and pass-through securities [Member]            
Investment disclosure details            
Fixed maturities, amortized cost 12,647     13,094    
Allowance for expected credit losses 0     0    
Gross unrealized gains 145     268    
Gross unrealized losses 173     130    
Fixed maturities, at fair value 12,619     13,232    
Corporate and all other bonds [Member]            
Investment disclosure details            
Fixed maturities, amortized cost 44,548     41,564    
Allowance for expected credit losses 2 $ 4 $ 3 3 $ 4 $ 2
Gross unrealized gains 185     458    
Gross unrealized losses 1,163     965    
Fixed maturities, at fair value $ 43,568     $ 41,054