v3.26.1
Investments (Narrative) (Details)
$ in Millions
3 Months Ended
Mar. 31, 2026
USD ($)
securities
Mar. 31, 2025
USD ($)
Dec. 31, 2025
USD ($)
securities
Investment Narrative [Line Items]      
Securities As Percentage Of Consolidated Stockholder Equity 10.00%    
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total 100.00%   100.00%
Funds withheld at interest $ 8,390   $ 8,149
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | securities 7,588,000   5,968
Financing Receivable, before Allowance for Credit Loss $ 11,477   $ 11,268
Financing Receivable, Modified in Period, Amount 13 $ 19  
Financial Asset, Equal to or Greater than 90 Days Past Due      
Investment Narrative [Line Items]      
Financing Receivable, before Allowance for Credit Loss $ 4 $ 6  
CALIFORNIA      
Investment Narrative [Line Items]      
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total 11.70%    
TEXAS      
Investment Narrative [Line Items]      
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total 9.70%    
CANADA      
Investment Narrative [Line Items]      
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total 6.40%    
UNITED KINGDOM      
Investment Narrative [Line Items]      
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total 1.90%    
UNITED STATES      
Investment Narrative [Line Items]      
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total 91.70%    
UTAH      
Investment Narrative [Line Items]      
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total 6.10%