v3.25.2
Reserve for Property and Casualty Insurance Claims and Claims Expense - Schedule of Rollforward of the Reserve for Property and Casualty Insurance Claims and Claims Expense (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Dec. 31, 2023
Property-liability insurance claims and claims expense            
Beginning balance     $ 41,917      
Incurred claims and claims expense related to:            
Prior years $ (370) $ (203) (621) $ (354)    
Claims and claims expense paid related to:            
Ending balance 44,141   44,141      
Property and casualty            
Property-liability insurance claims and claims expense            
Beginning balance     41,917 39,858    
Less: recoverables 9,285 8,341 9,285 8,341 $ 8,602 $ 8,396
Activity in the reserve for property-liability insurance claims and claims expense:            
Net beginning balance     33,315 31,462    
Incurred claims and claims expense related to:            
Current year     21,685 20,656    
Prior years     (621) (354)    
Total incurred     21,064 20,302    
Claims and claims expense paid related to:            
Current year     (10,002) (9,087)    
Prior years     (9,521) (9,465)    
Total paid     (19,523) (18,552)    
Net ending balance 34,856 33,212 34,856 33,212    
Plus: recoverables 9,285 8,341 9,285 8,341 $ 8,602 $ 8,396
Ending balance $ 44,141 $ 41,553 $ 44,141 $ 41,553