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Insurance - Short-duration insurance contracts, claims development (Details) - Property and casualty insurance $ in Millions | Dec. 31, 2021 USD ($) claim | Dec. 31, 2020 USD ($) | 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 ($) | Dec. 31, 2012 USD ($)
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Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 22,651 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | 16,632 |  |  |  |  |  |  |  |  |
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) | 436 |  |  |  |  |  |  |  |  |
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) | 6,455 |  |  |  |  |  |  |  |  |
Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | 1,866 | $ 1,875 | $ 1,886 | $ 1,906 | $ 1,941 | $ 1,955 | $ 1,947 | $ 1,946 | $ 1,952 | $ 1,970
Total IBNR Plus Expected Development on Reported Claims | $ 29 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 219,065 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 1,815 | 1,805 | 1,788 | 1,785 | 1,735 | 1,675 | 1,579 | 1,418 | 1,214 | 824
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 97.30% |  |  |  |  |  |  |  |  |
Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 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 | $ 42 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 222,550 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 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 | 96.00% |  |  |  |  |  |  |  |  |
Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,954 | 1,957 | 1,978 | 2,004 | 2,038 | 2,040 | 2,050 | 2,083 |  |
Total IBNR Plus Expected Development on Reported Claims | $ 64 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 219,626 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 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 | 94.50% |  |  |  |  |  |  |  |  |
Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 2,003 | 2,013 | 2,022 | 2,038 | 2,041 | 2,047 | 2,114 |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 85 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 230,625 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 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 | 92.20% |  |  |  |  |  |  |  |  |
Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 2,004 | 2,034 | 2,060 | 2,082 | 2,083 | 2,117 |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 156 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 222,755 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 1,750 | 1,662 | 1,539 | 1,350 | 1,099 | 577 |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 87.30% |  |  |  |  |  |  |  |  |
Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 2,269 | 2,301 | 2,329 | 2,348 | 2,375 |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 239 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 246,470 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 1,844 | 1,736 | 1,524 | 1,250 | 709 |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 81.30% |  |  |  |  |  |  |  |  |
Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 2,439 | 2,499 | 2,516 | 2,507 |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 382 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 235,776 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 1,807 | 1,606 | 1,337 | 730 |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 74.10% |  |  |  |  |  |  |  |  |
Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 2,672 | 2,674 | 2,721 |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 574 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 253,599 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 1,768 | 1,448 | 847 |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 66.20% |  |  |  |  |  |  |  |  |
Accident year 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 2,635 | 2,748 |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 898 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 202,683 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 1,337 | 758 |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 50.70% |  |  |  |  |  |  |  |  |
Accident Year 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 2,861 |  |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 1,531 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 179,651 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 746 |  |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 26.10% |  |  |  |  |  |  |  |  |
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) | $ 6,019 |  |  |  |  |  |  |  |  |
Property and transportation |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | 8,841 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | 7,546 |  |  |  |  |  |  |  |  |
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) | 23 |  |  |  |  |  |  |  |  |
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) | 1,318 |  |  |  |  |  |  |  |  |
Property and transportation | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | 877 | 879 | 881 | 886 | 890 | 894 | 883 | 871 | 857 | 864
Total IBNR Plus Expected Development on Reported Claims | $ 3 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 143,144 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 873 | 872 | 869 | 882 | 856 | 842 | 816 | 772 | 708 | 572
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 99.50% |  |  |  |  |  |  |  |  |
Property and transportation | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 870 | 871 | 873 | 877 | 878 | 878 | 872 | 870 | 882 |
Total IBNR Plus Expected Development on Reported Claims | $ 5 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 138,947 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 861 | 860 | 858 | 847 | 831 | 804 | 760 | 702 | 438 |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 99.00% |  |  |  |  |  |  |  |  |
Property and transportation | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 802 | 804 | 808 | 815 | 820 | 817 | 828 | 844 |  |
Total IBNR Plus Expected Development on Reported Claims | $ 6 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 133,218 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 791 | 789 | 783 | 770 | 744 | 693 | 632 | 329 |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 98.60% |  |  |  |  |  |  |  |  |
Property and transportation | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 768 | 772 | 777 | 777 | 779 | 784 | 818 |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 9 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 134,923 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 750 | 744 | 736 | 707 | 667 | 582 | 359 |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 97.70% |  |  |  |  |  |  |  |  |
Property and transportation | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 688 | 694 | 706 | 714 | 716 | 746 |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 15 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 121,191 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 656 | 640 | 618 | 577 | 521 | 294 |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 95.30% |  |  |  |  |  |  |  |  |
Property and transportation | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 816 | 823 | 843 | 847 | 889 |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 19 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 140,714 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 755 | 735 | 696 | 640 | 379 |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 92.50% |  |  |  |  |  |  |  |  |
Property and transportation | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 876 | 886 | 902 | 932 |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 35 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 130,271 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 781 | 738 | 676 | 396 |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 89.20% |  |  |  |  |  |  |  |  |
Property and transportation | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,051 | 1,058 | 1,111 |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 65 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 153,560 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 904 | 823 | 527 |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 86.00% |  |  |  |  |  |  |  |  |
Property and transportation | Accident year 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 974 | 1,043 |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 138 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 120,696 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 726 | 461 |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 74.50% |  |  |  |  |  |  |  |  |
Property and transportation | Accident Year 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,119 |  |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 397 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 108,153 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 449 |  |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 40.10% |  |  |  |  |  |  |  |  |
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) | $ 1,295 |  |  |  |  |  |  |  |  |
Specialty casualty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | 11,217 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | 7,153 |  |  |  |  |  |  |  |  |
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) | 383 |  |  |  |  |  |  |  |  |
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) | 4,447 |  |  |  |  |  |  |  |  |
Specialty casualty | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | 826 | 833 | 842 | 849 | 877 | 883 | 885 | 885 | 892 | 901
Total IBNR Plus Expected Development on Reported Claims | $ 23 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 54,827 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 783 | 775 | 761 | 745 | 723 | 684 | 621 | 516 | 385 | 173
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 94.80% |  |  |  |  |  |  |  |  |
Specialty casualty | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 898 | 905 | 916 | 926 | 945 | 940 | 945 | 949 | 968 |
Total IBNR Plus Expected Development on Reported Claims | $ 35 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 55,128 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 835 | 820 | 797 | 766 | 729 | 666 | 554 | 396 | 182 |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 93.00% |  |  |  |  |  |  |  |  |
Specialty casualty | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 950 | 952 | 967 | 982 | 1,006 | 1,008 | 1,008 | 1,035 |  |
Total IBNR Plus Expected Development on Reported Claims | $ 50 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 56,942 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 862 | 829 | 801 | 755 | 680 | 574 | 412 | 190 |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 90.70% |  |  |  |  |  |  |  |  |
Specialty casualty | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,015 | 1,021 | 1,024 | 1,042 | 1,041 | 1,043 | 1,081 |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 67 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 58,076 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 888 | 844 | 792 | 702 | 577 | 411 | 178 |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 87.50% |  |  |  |  |  |  |  |  |
Specialty casualty | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,069 | 1,090 | 1,101 | 1,116 | 1,122 | 1,131 |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 124 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 56,407 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 870 | 806 | 713 | 584 | 418 | 186 |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 81.40% |  |  |  |  |  |  |  |  |
Specialty casualty | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,162 | 1,189 | 1,204 | 1,221 | 1,211 |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 200 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 56,975 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 833 | 755 | 612 | 422 | 200 |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 71.70% |  |  |  |  |  |  |  |  |
Specialty casualty | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,262 | 1,302 | 1,307 | 1,277 |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 297 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 58,808 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 794 | 649 | 475 | 210 |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 62.90% |  |  |  |  |  |  |  |  |
Specialty casualty | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,322 | 1,311 | 1,308 |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 442 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 58,304 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 651 | 455 | 212 |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 49.20% |  |  |  |  |  |  |  |  |
Specialty casualty | Accident year 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,329 | 1,352 |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 631 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 52,733 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 446 | 188 |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 33.60% |  |  |  |  |  |  |  |  |
Specialty casualty | Accident Year 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 1,384 |  |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 907 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 48,149 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 191 |  |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 13.80% |  |  |  |  |  |  |  |  |
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) | $ 4,064 |  |  |  |  |  |  |  |  |
Specialty financial |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | 1,726 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | 1,468 |  |  |  |  |  |  |  |  |
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) | (2) |  |  |  |  |  |  |  |  |
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) | 256 |  |  |  |  |  |  |  |  |
Specialty financial | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | 125 | 126 | 127 | 132 | 135 | 137 | 139 | 151 | 163 | 163
Total IBNR Plus Expected Development on Reported Claims | $ 1 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 21,094 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 125 | 125 | 126 | 128 | 126 | 121 | 117 | 109 | 104 | 71
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 100.00% |  |  |  |  |  |  |  |  |
Specialty financial | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 120 | 122 | 122 | 126 | 127 | 131 | 137 | 145 | 140 |
Total IBNR Plus Expected Development on Reported Claims | $ 1 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 28,475 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 118 | 118 | 118 | 117 | 117 | 113 | 107 | 100 | 70 |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 98.30% |  |  |  |  |  |  |  |  |
Specialty financial | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 136 | 137 | 142 | 147 | 153 | 156 | 157 | 146 |  |
Total IBNR Plus Expected Development on Reported Claims | $ 1 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 29,466 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 140 | 141 | 139 | 137 | 128 | 125 | 109 | 62 |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 102.90% |  |  |  |  |  |  |  |  |
Specialty financial | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 136 | 138 | 145 | 153 | 158 | 160 | 156 |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 2 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 37,626 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 134 | 134 | 132 | 133 | 129 | 110 | 72 |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 98.50% |  |  |  |  |  |  |  |  |
Specialty financial | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 170 | 174 | 182 | 187 | 184 | 179 |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 4 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 45,157 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 164 | 163 | 161 | 158 | 141 | 88 |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 96.50% |  |  |  |  |  |  |  |  |
Specialty financial | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 203 | 208 | 212 | 215 | 212 |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 8 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 48,781 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 193 | 194 | 186 | 169 | 120 |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 95.10% |  |  |  |  |  |  |  |  |
Specialty financial | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 207 | 219 | 217 | 212 |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 15 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 46,697 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 188 | 187 | 163 | 112 |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 90.80% |  |  |  |  |  |  |  |  |
Specialty financial | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 191 | 198 | 194 |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 23 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 41,735 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 164 | 146 | 99 |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 85.90% |  |  |  |  |  |  |  |  |
Specialty financial | Accident year 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 215 | 231 |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 49 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 29,254 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 144 | 100 |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 67.00% |  |  |  |  |  |  |  |  |
Specialty financial | Accident Year 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 223 |  |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 110 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 23,349 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 98 |  |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 43.90% |  |  |  |  |  |  |  |  |
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) | $ 258 |  |  |  |  |  |  |  |  |
Other specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | 867 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | 465 |  |  |  |  |  |  |  |  |
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE) | 32 |  |  |  |  |  |  |  |  |
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE) | 434 |  |  |  |  |  |  |  |  |
Other specialty | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | 38 | 37 | 36 | 39 | 39 | 41 | 40 | 39 | 40 | 42
Total IBNR Plus Expected Development on Reported Claims | $ 2 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 34 | 33 | 32 | 30 | 30 | 28 | 25 | 21 | 17 | $ 8
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 89.50% |  |  |  |  |  |  |  |  |
Other specialty | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 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 | $ 57 | 53 | 51 | 44 | 37 | 34 | 22 | 16 | $ 7 |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 95.00% |  |  |  |  |  |  |  |  |
Other specialty | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 66 | 64 | 61 | 60 | 59 | 59 | 57 | 58 |  |
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 | $ 54 | 53 | 50 | 43 | 36 | 30 | 21 | $ 13 |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 81.80% |  |  |  |  |  |  |  |  |
Other specialty | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 84 | 82 | 76 | 66 | 63 | 60 | 59 |  |  |
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 | $ 75 | 69 | 62 | 50 | 31 | 26 | $ 10 |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 89.30% |  |  |  |  |  |  |  |  |
Other specialty | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 77 | 76 | 71 | 65 | 61 | 61 |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 13 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 60 | 53 | 47 | 31 | 19 | $ 9 |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 77.90% |  |  |  |  |  |  |  |  |
Other specialty | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 88 | 81 | 70 | 65 | 63 |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 12 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 63 | 52 | 30 | 19 | $ 10 |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 71.60% |  |  |  |  |  |  |  |  |
Other specialty | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 94 | 92 | 90 | 86 |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 35 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 44 | 32 | 23 | $ 12 |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 46.80% |  |  |  |  |  |  |  |  |
Other specialty | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 108 | 107 | 108 |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 44 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 49 | 24 | $ 9 |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 45.40% |  |  |  |  |  |  |  |  |
Other specialty | Accident year 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 117 | 122 |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 80 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 21 | $ 9 |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 17.90% |  |  |  |  |  |  |  |  |
Other specialty | Accident Year 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated LAE, Net of Reinsurance | $ 135 |  |  |  |  |  |  |  |  |
Total IBNR Plus Expected Development on Reported Claims | $ 117 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance | $ 8 |  |  |  |  |  |  |  |  |
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance | 5.90% |  |  |  |  |  |  |  |  |
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) | $ 402 |  |  |  |  |  |  |  |  |

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