XML 126 R104.htm IDEA: XBRL DOCUMENT v3.22.4
Insurance - Short-duration insurance contracts, claims development (Details) - Property and casualty insurance
$ in Millions
Dec. 31, 2022
USD ($)
claim
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Dec. 31, 2013
USD ($)
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 23,798                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance 17,245                  
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) 418                  
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) 6,971                  
Accident Year 2013                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance 1,946 $ 1,948 $ 1,956 $ 1,969 $ 1,982 $ 2,000 $ 1,996 $ 2,000 $ 2,011 $ 2,036
Total IBNR Plus Expected Development on Reported Claims $ 34                  
Cumulative Number of Reported Claims | claim 222,729                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 1,886 1,871 1,851 1,824 1,774 1,714 1,617 1,443 1,214 697
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 96.90%                  
Accident Year 2014                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,958 1,954 1,957 1,978 2,004 2,038 2,040 2,050 2,083  
Total IBNR Plus Expected Development on Reported Claims $ 45                  
Cumulative Number of Reported Claims | claim 219,890                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 1,870 1,847 1,812 1,773 1,705 1,588 1,422 1,174 594  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 95.50%                  
Accident Year 2015                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,998 2,003 2,013 2,022 2,038 2,041 2,047 2,114    
Total IBNR Plus Expected Development on Reported Claims $ 62                  
Cumulative Number of Reported Claims | claim 230,926                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 1,878 1,847 1,791 1,722 1,592 1,404 1,129 619    
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 94.00%                  
Accident Year 2016                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,986 2,004 2,034 2,060 2,082 2,083 2,117      
Total IBNR Plus Expected Development on Reported Claims $ 104                  
Cumulative Number of Reported Claims | claim 223,087                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 1,806 1,750 1,662 1,539 1,350 1,099 577      
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 90.90%                  
Accident Year 2017                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 2,256 2,269 2,301 2,329 2,348 2,375        
Total IBNR Plus Expected Development on Reported Claims $ 165                  
Cumulative Number of Reported Claims | claim 246,965                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 1,953 1,844 1,736 1,524 1,250 709        
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 86.60%                  
Accident Year 2018                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 2,452 2,439 2,499 2,516 2,507          
Total IBNR Plus Expected Development on Reported Claims $ 283                  
Cumulative Number of Reported Claims | claim 236,583                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 1,977 1,807 1,606 1,337 730          
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 80.60%                  
Accident Year 2019                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 2,632 2,672 2,674 2,721            
Total IBNR Plus Expected Development on Reported Claims $ 382                  
Cumulative Number of Reported Claims | claim 254,938                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 1,983 1,768 1,448 847            
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 75.30%                  
Accident year 2020                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 2,546 2,635 2,748              
Total IBNR Plus Expected Development on Reported Claims $ 596                  
Cumulative Number of Reported Claims | claim 204,670                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 1,620 1,337 758              
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 63.60%                  
Accident Year 2021                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 2,754 2,861                
Total IBNR Plus Expected Development on Reported Claims $ 969                  
Cumulative Number of Reported Claims | claim 203,562                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 1,368 746                
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 49.70%                  
Accident Year 2022                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 3,270                  
Total IBNR Plus Expected Development on Reported Claims $ 1,636                  
Cumulative Number of Reported Claims | claim 190,857                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 904                  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 27.60%                  
Excludes short-duration insurance contracts detail for accident years not separately presented                    
Claims Development [Line Items]                    
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) $ 6,553                  
Property and transportation                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance 9,258                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance 7,800                  
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) 23                  
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) 1,481                  
Property and transportation | Accident Year 2013                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance 870 870 871 873 877 878 878 872 870 882
Total IBNR Plus Expected Development on Reported Claims $ 4                  
Cumulative Number of Reported Claims | claim 139,031                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 864 861 860 858 847 831 804 760 702 438
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 99.30%                  
Property and transportation | Accident Year 2014                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 800 802 804 808 815 820 817 828 844  
Total IBNR Plus Expected Development on Reported Claims $ 5                  
Cumulative Number of Reported Claims | claim 133,262                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 792 791 789 783 770 744 693 632 329  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 99.00%                  
Property and transportation | Accident Year 2015                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 769 768 772 777 777 779 784 818    
Total IBNR Plus Expected Development on Reported Claims $ 7                  
Cumulative Number of Reported Claims | claim 135,048                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 755 750 744 736 707 667 582 359    
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 98.20%                  
Property and transportation | Accident Year 2016                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 689 688 694 706 714 716 746      
Total IBNR Plus Expected Development on Reported Claims $ 9                  
Cumulative Number of Reported Claims | claim 121,361                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 665 656 640 618 577 521 294      
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 96.50%                  
Property and transportation | Accident Year 2017                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 820 816 823 843 847 889        
Total IBNR Plus Expected Development on Reported Claims $ 15                  
Cumulative Number of Reported Claims | claim 140,902                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 783 755 735 696 640 379        
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 95.50%                  
Property and transportation | Accident Year 2018                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 882 876 886 902 932          
Total IBNR Plus Expected Development on Reported Claims $ 24                  
Cumulative Number of Reported Claims | claim 130,600                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 824 781 738 676 396          
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 93.40%                  
Property and transportation | Accident Year 2019                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,055 1,051 1,058 1,111            
Total IBNR Plus Expected Development on Reported Claims $ 35                  
Cumulative Number of Reported Claims | claim 154,011                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 959 904 823 527            
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 90.90%                  
Property and transportation | Accident year 2020                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 957 974 1,043              
Total IBNR Plus Expected Development on Reported Claims $ 71                  
Cumulative Number of Reported Claims | claim 121,649                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 804 726 461              
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 84.00%                  
Property and transportation | Accident Year 2021                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,023 1,119                
Total IBNR Plus Expected Development on Reported Claims $ 129                  
Cumulative Number of Reported Claims | claim 122,024                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 767 449                
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 75.00%                  
Property and transportation | Accident Year 2022                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,393                  
Total IBNR Plus Expected Development on Reported Claims $ 436                  
Cumulative Number of Reported Claims | claim 122,637                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 587                  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 42.10%                  
Property and transportation | Excludes short-duration insurance contracts detail for accident years not separately presented                    
Claims Development [Line Items]                    
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) $ 1,458                  
Specialty casualty                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance 11,713                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance 7,392                  
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) 367                  
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) 4,688                  
Specialty casualty | Accident Year 2013                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance 895 898 905 916 926 945 940 945 949 968
Total IBNR Plus Expected Development on Reported Claims $ 28                  
Cumulative Number of Reported Claims | claim 55,221                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 845 835 820 797 766 729 666 554 396 182
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 94.40%                  
Specialty casualty | Accident Year 2014                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 955 950 952 967 982 1,006 1,008 1,008 1,035  
Total IBNR Plus Expected Development on Reported Claims $ 36                  
Cumulative Number of Reported Claims | claim 57,158                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 881 862 829 801 755 680 574 412 190  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 92.30%                  
Specialty casualty | Accident Year 2015                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,007 1,015 1,021 1,024 1,042 1,041 1,043 1,081    
Total IBNR Plus Expected Development on Reported Claims $ 49                  
Cumulative Number of Reported Claims | claim 58,251                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 913 888 844 792 702 577 411 178    
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 90.70%                  
Specialty casualty | Accident Year 2016                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,046 1,069 1,090 1,101 1,116 1,122 1,131      
Total IBNR Plus Expected Development on Reported Claims $ 83                  
Cumulative Number of Reported Claims | claim 56,549                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 906 870 806 713 584 418 186      
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 86.60%                  
Specialty casualty | Accident Year 2017                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,139 1,162 1,189 1,204 1,221 1,211        
Total IBNR Plus Expected Development on Reported Claims $ 139                  
Cumulative Number of Reported Claims | claim 57,232                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 902 833 755 612 422 200        
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 79.20%                  
Specialty casualty | Accident Year 2018                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,269 1,262 1,302 1,307 1,277          
Total IBNR Plus Expected Development on Reported Claims $ 226                  
Cumulative Number of Reported Claims | claim 59,219                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 901 794 649 475 210          
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 71.00%                  
Specialty casualty | Accident Year 2019                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,280 1,322 1,311 1,308            
Total IBNR Plus Expected Development on Reported Claims $ 300                  
Cumulative Number of Reported Claims | claim 59,029                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 795 651 455 212            
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 62.10%                  
Specialty casualty | Accident year 2020                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,258 1,329 1,352              
Total IBNR Plus Expected Development on Reported Claims $ 440                  
Cumulative Number of Reported Claims | claim 53,383                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 613 446 188              
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 48.70%                  
Specialty casualty | Accident Year 2021                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,389 1,384                
Total IBNR Plus Expected Development on Reported Claims $ 696                  
Cumulative Number of Reported Claims | claim 54,555                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 438 191                
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 31.50%                  
Specialty casualty | Accident Year 2022                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 1,475                  
Total IBNR Plus Expected Development on Reported Claims $ 954                  
Cumulative Number of Reported Claims | claim 48,805                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 198                  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 13.40%                  
Specialty casualty | Excludes short-duration insurance contracts detail for accident years not separately presented                    
Claims Development [Line Items]                    
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) $ 4,321                  
Specialty financial                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance 1,796                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance 1,518                  
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) (1)                  
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) 277                  
Specialty financial | Accident Year 2013                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance 118 120 122 122 126 127 131 137 145 140
Total IBNR Plus Expected Development on Reported Claims $ 1                  
Cumulative Number of Reported Claims | claim 28,477                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 117 118 118 118 117 117 113 107 100 70
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 99.20%                  
Specialty financial | Accident Year 2014                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 135 136 137 142 147 153 156 157 146  
Total IBNR Plus Expected Development on Reported Claims $ 1                  
Cumulative Number of Reported Claims | claim 29,470                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 141 140 141 139 137 128 125 109 62  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 104.40%                  
Specialty financial | Accident Year 2015                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 135 136 138 145 153 158 160 156    
Total IBNR Plus Expected Development on Reported Claims $ 1                  
Cumulative Number of Reported Claims | claim 37,627                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 134 134 134 132 133 129 110 72    
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 99.30%                  
Specialty financial | Accident Year 2016                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 173 170 174 182 187 184 179      
Total IBNR Plus Expected Development on Reported Claims $ 2                  
Cumulative Number of Reported Claims | claim 45,177                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 171 164 163 161 158 141 88      
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 98.80%                  
Specialty financial | Accident Year 2017                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 202 203 208 212 215 212        
Total IBNR Plus Expected Development on Reported Claims $ 4                  
Cumulative Number of Reported Claims | claim 48,831                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 192 193 194 186 169 120        
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 95.00%                  
Specialty financial | Accident Year 2018                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 201 207 219 217 212          
Total IBNR Plus Expected Development on Reported Claims $ 7                  
Cumulative Number of Reported Claims | claim 46,764                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 192 188 187 163 112          
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 95.50%                  
Specialty financial | Accident Year 2019                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 186 191 198 194            
Total IBNR Plus Expected Development on Reported Claims $ 15                  
Cumulative Number of Reported Claims | claim 41,898                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 168 164 146 99            
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 90.30%                  
Specialty financial | Accident year 2020                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 202 215 231              
Total IBNR Plus Expected Development on Reported Claims $ 23                  
Cumulative Number of Reported Claims | claim 29,638                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 159 144 100              
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 78.70%                  
Specialty financial | Accident Year 2021                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 201 223                
Total IBNR Plus Expected Development on Reported Claims $ 49                  
Cumulative Number of Reported Claims | claim 26,983                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 136 98                
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 67.70%                  
Specialty financial | Accident Year 2022                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 243                  
Total IBNR Plus Expected Development on Reported Claims $ 124                  
Cumulative Number of Reported Claims | claim 19,415                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 108                  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 44.40%                  
Specialty financial | Excludes short-duration insurance contracts detail for accident years not separately presented                    
Claims Development [Line Items]                    
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) $ 278                  
Other specialty                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance 1,031                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance 535                  
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) 29                  
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) 525                  
Other specialty | Accident Year 2013                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance 63 60 58 58 53 50 47 46 47 46
Total IBNR Plus Expected Development on Reported Claims $ 1                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 60 57 53 51 44 37 34 22 16 $ 7
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 95.20%                  
Other specialty | Accident Year 2014                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 68 66 64 61 60 59 59 57 58  
Total IBNR Plus Expected Development on Reported Claims $ 3                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 56 54 53 50 43 36 30 21 $ 13  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 82.40%                  
Other specialty | Accident Year 2015                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 87 84 82 76 66 63 60 59    
Total IBNR Plus Expected Development on Reported Claims $ 5                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 76 75 69 62 50 31 26 $ 10    
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 87.40%                  
Other specialty | Accident Year 2016                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 78 77 76 71 65 61 61      
Total IBNR Plus Expected Development on Reported Claims $ 10                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 64 60 53 47 31 19 $ 9      
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 82.10%                  
Other specialty | Accident Year 2017                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 95 88 81 70 65 63        
Total IBNR Plus Expected Development on Reported Claims $ 7                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 76 63 52 30 19 $ 10        
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 80.00%                  
Other specialty | Accident Year 2018                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 100 94 92 90 86          
Total IBNR Plus Expected Development on Reported Claims $ 26                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 60 44 32 23 $ 12          
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 60.00%                  
Other specialty | Accident Year 2019                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 111 108 107 108            
Total IBNR Plus Expected Development on Reported Claims $ 32                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 61 49 24 $ 9            
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 55.00%                  
Other specialty | Accident year 2020                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 129 117 122              
Total IBNR Plus Expected Development on Reported Claims $ 62                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 44 21 $ 9              
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 34.10%                  
Other specialty | Accident Year 2021                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 141 135                
Total IBNR Plus Expected Development on Reported Claims $ 95                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 27 $ 8                
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 19.10%                  
Other specialty | Accident Year 2022                    
Claims Development [Line Items]                    
Incurred Claims and Allocated LAE, Net of Reinsurance $ 159                  
Total IBNR Plus Expected Development on Reported Claims $ 122                  
Cumulative Number of Reported Claims | claim 0                  
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance $ 11                  
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance 6.90%                  
Other specialty | Excludes short-duration insurance contracts detail for accident years not separately presented                    
Claims Development [Line Items]                    
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) $ 496