XML 191 R123.htm IDEA: XBRL DOCUMENT v3.24.0.1
Reserve for Unpaid Losses and Loss Adjustment Expenses - PC Additional Information (Details) - USD ($)
$ in Millions
 12 Months Ended 84 Months Ended
Apr. 20, 2023
May 23, 2019
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2016
Dec. 31, 2023
Dec. 31, 2020
Liability for Claims and Claims Adjustment Expense [Line Items]                
Benefits, losses and loss adjustment expenses     $ 14,238 $ 13,138 $ 12,720      
Unpaid losses and loss adjustment expenses     42,318 41,243     $ 42,318  
Asbestos and Environmental                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Liability for Asbestos and Environmental Claims, Gross, Period Increase (Decrease)     194 229 155      
Change in Deferred Gain on Retroactive Reinsurance     194 229 155      
Adverse development from comprehensive annual review             1,438  
Net asbestos reserves                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Prior accident year development [1]     156 162 106      
Net environmental reserves                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Prior accident year development [1]     38 67 49      
Reinsurance Policy, Type [Axis]: Adverse Development Cover Navigators Group                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Change in Deferred Gain on Retroactive Reinsurance     0 0 91      
Adverse development from comprehensive annual review     300          
Reinsurance premium   $ 91            
Deferred Revenue     209       209  
Reinsurance Policy, Type [Axis]: Asbestos and Environmental | Asbestos and Environmental                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Adverse development from comprehensive annual review     1,438          
Reinsurance premium           $ 650    
Deferred Revenue     788       788  
General liability | Abuse Claims [Member]                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Unpaid losses and loss adjustment expenses     787       787  
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years $ 787              
General liability | Reinsurance Policy, Type [Axis]: Adverse Development Cover Navigators Group                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Adverse development from comprehensive annual review     105          
Property and Casualty Insurance Subsidiaries                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Prior accident year development [1]     10 36 199      
Adverse development from comprehensive annual review     1,043 1,338 1,243      
Unpaid losses and loss adjustment expenses     34,044 33,083 31,449   $ 34,044 $ 29,622
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years     5,926 4,678 4,119      
Property and Casualty Insurance Subsidiaries | Reinsurance Policy, Type [Axis]: Adverse Development Cover Navigators Group                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Change in Deferred Gain on Retroactive Reinsurance     194 $ 229 $ 246      
Automobile | Reinsurance Policy, Type [Axis]: Adverse Development Cover Navigators Group | P&C Commercial Lines                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Adverse development from comprehensive annual review     $ 14          
Maximum | Property and Casualty Insurance Subsidiaries                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Weighted average discount rate     14.03% 14.03% 14.03%   14.03%  
Minimum [Member] | Property and Casualty Insurance Subsidiaries                
Liability for Claims and Claims Adjustment Expense [Line Items]                
Weighted average discount rate     0.83% 0.83% 0.83%   0.83%