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RESERVE FOR LOSSES AND LOSS EXPENSES - Incurred claims and allocated claim adjustment expenses, net of reinsurance (Details) $ in Thousands | Dec. 31, 2019 USD ($) claim | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($) | Dec. 31, 2012 USD ($) | Dec. 31, 2011 USD ($) | Dec. 31, 2010 USD ($)
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Insurance | Property and other |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 3,945,377 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 114,355 | $ 114,614 | $ 115,712 | $ 116,172 | $ 116,477 | $ 117,406 | $ 122,897 | $ 148,126 | $ 155,512 | $ 173,118
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 684 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,423 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 280,491 | 281,389 | 283,096 | 282,663 | 283,852 | 286,896 | 307,305 | 327,787 | 348,001 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ (18) |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 6,350 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 342,017 | 352,048 | 352,879 | 358,598 | 363,171 | 383,228 | 400,995 | 391,031 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 497 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 29,931 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 275,074 | 278,790 | 268,350 | 268,704 | 272,642 | 299,498 | 309,937 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 1,505 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 53,191 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 326,638 | 328,252 | 329,251 | 344,878 | 355,495 | 360,874 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 3,990 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 62,356 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 252,560 | 255,392 | 259,725 | 270,793 | 278,554 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 4,077 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 48,424 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 356,353 | 369,508 | 377,820 | 351,075 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 6,011 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 93,717 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 808,602 | 829,016 | 885,486 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 2,992 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 697,983 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 759,300 | 721,266 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 41,900 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 705,592 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 429,987 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 113,754 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 445,460 |  |  |  |  |  |  |  |  |
Insurance | Marine |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 1,020,047 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 44,696 | 45,064 | 45,482 | 47,226 | 48,618 | 51,482 | 53,458 | 66,359 | 70,314 | 68,519
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 262 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,197 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 68,330 | 69,011 | 68,318 | 66,156 | 65,921 | 65,973 | 72,875 | 78,807 | 90,776 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 976 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,830 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 62,447 | 73,002 | 74,797 | 72,238 | 71,211 | 69,075 | 83,138 | 89,712 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 2,718 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,134 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 81,070 | 82,073 | 82,487 | 97,250 | 96,164 | 100,757 | 79,578 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 1,174 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,353 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 47,574 | 46,030 | 44,420 | 48,586 | 44,576 | 59,686 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 4,249 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,163 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 117,587 | 129,914 | 137,180 | 141,317 | 160,063 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 3,079 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,228 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 71,161 | 76,511 | 78,762 | 86,386 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 4,020 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,841 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 166,796 | 170,775 | 173,222 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 27,726 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,976 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 191,005 | 182,232 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 45,347 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,232 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 169,381 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 94,818 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,525 |  |  |  |  |  |  |  |  |
Insurance | Aviation |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 291,275 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 8,836 | 8,868 | 8,525 | 8,741 | 8,695 | 8,766 | 9,745 | 11,420 | 11,698 | 12,917
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 48 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 663 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 6,952 | 7,192 | 7,234 | 7,277 | 8,424 | 9,555 | 12,781 | 15,391 | 17,724 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 118 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,202 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 7,392 | 7,599 | 7,712 | 7,769 | 8,718 | 10,801 | 10,677 | 12,793 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 83 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,857 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 16,763 | 15,470 | 15,585 | 15,249 | 15,205 | 16,330 | 15,652 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 255 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,017 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 19,088 | 21,847 | 21,789 | 24,349 | 23,033 | 20,435 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 493 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,529 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 27,512 | 29,567 | 29,833 | 28,502 | 29,782 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 299 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,140 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 31,723 | 33,658 | 33,502 | 29,173 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 606 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,062 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 66,896 | 62,035 | 55,581 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 3,747 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,272 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 63,753 | 57,990 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 6,841 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,258 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 42,360 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 11,632 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,305 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 395,724 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 99,633 | 99,423 | 90,888 | 72,104 | 65,014 | 64,980 | 65,597 | 63,259 | 63,179 | 62,415
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 339 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 6 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 27,904 | 27,904 | 33,609 | 45,036 | 48,333 | 48,361 | 47,706 | 48,665 | 58,154 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 268 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 198 | 198 | 46 | 10,322 | 12,447 | 12,435 | 15,672 | 32,602 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 155 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 12,377 | 14,067 | 14,942 | 9,880 | 9,759 | 25,684 | 26,439 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 4,070 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 71,274 | 69,589 | 68,324 | 67,109 | 70,713 | 38,825 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 2,822 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 6 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 25,930 | 26,012 | 27,524 | 30,368 | 30,329 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 2,621 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 42,972 | 42,401 | 44,891 | 45,391 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 18,275 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 28,209 | 34,765 | 36,751 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 17,808 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 36,618 | 47,215 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 12,576 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 50,609 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 33,702 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 5 |  |  |  |  |  |  |  |  |
Insurance | Professional lines |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 3,490,705 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 185,116 | 187,464 | 167,917 | 180,704 | 158,729 | 183,237 | 206,406 | 234,655 | 237,156 | 232,002
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 17,194 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 5,698 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 350,066 | 352,792 | 352,309 | 343,911 | 330,773 | 326,663 | 333,914 | 315,326 | 313,520 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 28,007 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 7,229 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 351,283 | 353,182 | 364,443 | 362,534 | 375,549 | 376,603 | 375,164 | 328,397 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 34,964 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 8,326 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 334,398 | 356,261 | 354,190 | 364,851 | 398,059 | 396,819 | 383,432 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 49,144 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 9,439 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 353,994 | 371,407 | 391,952 | 421,093 | 411,232 | 412,523 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 76,580 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 9,802 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 344,239 | 357,646 | 382,679 | 376,865 | 377,129 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 87,707 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 10,453 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 359,813 | 358,368 | 351,990 | 349,030 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 105,971 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 11,763 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 437,528 | 397,760 | 378,746 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 197,748 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 13,418 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 374,683 | 361,490 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 217,867 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 15,584 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 399,585 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 348,212 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 11,747 |  |  |  |  |  |  |  |  |
Insurance | Liability |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 1,336,252 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 107,420 | 104,042 | 104,465 | 105,438 | 98,529 | 100,133 | 98,853 | 98,642 | 94,222 | 79,398
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 12,287 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,029 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 85,036 | 82,657 | 82,312 | 84,079 | 85,792 | 87,770 | 83,925 | 75,329 | 72,580 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 14,042 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,571 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 67,237 | 72,727 | 75,697 | 68,658 | 71,474 | 74,134 | 71,683 | 70,887 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 18,015 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,188 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 91,941 | 95,981 | 93,681 | 88,241 | 95,174 | 95,306 | 93,233 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 16,997 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,568 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 131,474 | 132,019 | 130,672 | 129,764 | 124,303 | 107,133 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 22,710 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,865 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 183,088 | 165,073 | 137,568 | 127,353 | 128,437 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 43,822 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 6,225 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 127,528 | 128,911 | 130,188 | 124,323 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 53,401 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 7,068 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 183,793 | 166,573 | 162,446 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 76,834 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 6,710 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 167,614 | 168,146 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 95,288 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 5,454 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 191,121 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 165,431 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,714 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 7,226,127 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 566,112 | 567,879 | 568,725 | 570,796 | 578,740 | 584,942 | 581,838 | 570,057 | 601,243 | 614,748
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 3,070 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,041,771 | 1,040,759 | 1,039,379 | 1,041,136 | 1,067,100 | 1,084,197 | 1,116,042 | 1,116,669 | 1,111,563 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 7,782 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 454,281 | 457,531 | 456,127 | 461,152 | 476,989 | 507,619 | 523,208 | 555,459 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 2,860 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 499,736 | 503,026 | 503,539 | 509,526 | 529,856 | 560,658 | 578,725 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 1,904 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 519,529 | 520,299 | 522,102 | 534,618 | 560,775 | 542,601 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 40,234 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 450,182 | 454,225 | 459,487 | 464,588 | 477,301 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 6,030 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 618,643 | 622,331 | 635,164 | 616,621 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 11,017 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,107,597 | 1,081,415 | 1,076,967 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 75,459 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,008,505 | 882,829 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 166,887 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 959,771 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 729,042 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,862,842 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 167,376 | 166,044 | 179,762 | 189,415 | 196,939 | 214,185 | 214,417 | 211,361 | 210,173 | 209,934
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 5,701 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 166,951 | 177,405 | 200,437 | 208,219 | 209,088 | 211,367 | 202,620 | 201,364 | 201,013 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 6,047 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 206,791 | 213,984 | 212,594 | 222,626 | 223,926 | 221,544 | 216,088 | 209,548 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 18,318 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 181,563 | 205,733 | 213,182 | 213,745 | 215,562 | 214,396 | 209,292 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 35,871 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 230,042 | 233,611 | 219,242 | 219,345 | 219,415 | 219,376 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 27,940 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 231,980 | 225,139 | 214,344 | 212,024 | 212,031 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 63,050 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 227,952 | 200,020 | 196,293 | 195,190 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 67,496 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 162,116 | 155,759 | 155,137 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 72,727 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 148,921 | 146,387 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 132,683 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 139,150 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 130,571 |  |  |  |  |  |  |  |  |
Reinsurance | Liability |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 2,136,911 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 156,113 | 159,230 | 165,983 | 181,962 | 190,921 | 202,007 | 183,715 | 183,347 | 171,775 | 172,823
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 13,119 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 189,014 | 191,873 | 193,784 | 194,604 | 197,766 | 191,668 | 173,984 | 172,201 | 172,189 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 16,614 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 158,342 | 164,309 | 170,979 | 173,501 | 172,341 | 167,366 | 162,945 | 166,386 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 16,994 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 157,236 | 177,112 | 183,915 | 184,240 | 182,201 | 175,174 | 171,271 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 24,545 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 197,187 | 199,340 | 200,557 | 204,657 | 202,939 | 199,433 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 53,905 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 213,662 | 215,889 | 216,061 | 215,099 | 214,735 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 67,030 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 254,154 | 250,868 | 245,820 | 240,440 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 99,784 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 279,172 | 270,589 | 276,929 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 133,392 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 268,506 | 264,570 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 168,425 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 263,525 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 214,542 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,126,325 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 71,911 | 73,672 | 74,913 | 76,937 | 78,247 | 85,856 | 90,029 | 92,848 | 99,460 | 119,180
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 1,751 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 95,813 | 98,885 | 99,412 | 101,236 | 109,662 | 111,485 | 104,616 | 106,495 | 120,572 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 2,439 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 124,552 | 127,576 | 131,120 | 139,097 | 147,406 | 150,137 | 147,627 | 159,507 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 3,883 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 124,674 | 124,533 | 135,762 | 139,886 | 143,719 | 152,467 | 164,207 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 3,546 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 126,397 | 127,683 | 139,015 | 142,703 | 135,525 | 136,419 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 6,726 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 137,848 | 156,635 | 160,675 | 165,861 | 160,132 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 8,335 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 123,366 | 148,943 | 141,128 | 141,639 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 9,849 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 126,786 | 132,618 | 135,040 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 22,830 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 120,289 | 111,692 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 38,357 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 74,689 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 39,291 |  |  |  |  |  |  |  |  |
Reinsurance | Motor |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 2,182,564 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 80,028 | 80,901 | 83,112 | 86,803 | 96,235 | 101,343 | 107,264 | 108,183 | 107,538 | $ 100,219
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 21,660 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 136,077 | 143,846 | 148,536 | 159,626 | 168,225 | 172,062 | 166,112 | 162,069 | $ 158,475 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 18,030 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 126,507 | 134,685 | 137,585 | 147,041 | 151,899 | 159,446 | 170,848 | $ 180,137 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 15,534 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 126,050 | 135,003 | 137,791 | 141,237 | 150,620 | 162,475 | $ 164,927 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 13,828 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 171,403 | 174,719 | 179,510 | 182,237 | 186,947 | $ 185,279 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 6,302 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 216,610 | 227,844 | 226,319 | 222,178 | $ 225,974 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 12,291 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 259,959 | 270,264 | 268,525 | $ 249,616 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 21,855 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 362,721 | 380,509 | $ 370,778 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 50,597 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 363,733 | $ 363,917 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 83,024 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 339,476 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 165,127 |  |  |  |  |  |  |  |  |

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