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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, 2018 USD ($) claim | Dec. 31, 2017 USD ($) | 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 ($) | Dec. 31, 2009 USD ($)
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Insurance | Property and other |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 3,583,317 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 77,338 | $ 78,395 | $ 78,150 | $ 78,490 | $ 78,269 | $ 80,461 | $ 82,460 | $ 89,768 | $ 99,079 | $ 117,309
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 83 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,201 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 113,767 | 114,866 | 115,316 | 115,635 | 116,562 | 122,111 | 147,426 | 155,032 | 175,012 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 867 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,422 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 279,996 | 281,866 | 281,405 | 282,755 | 285,745 | 306,114 | 338,220 | 359,132 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 979 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 6,348 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 350,827 | 351,673 | 357,267 | 361,476 | 381,746 | 399,473 | 391,646 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 8,992 |  |  |  |  |  |  |  |  |
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 | $ 276,940 | 266,727 | 267,022 | 271,157 | 297,713 | 308,359 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 6,687 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 53,172 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 326,100 | 327,389 | 343,333 | 354,219 | 360,130 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 5,917 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 62,444 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 253,729 | 257,927 | 268,897 | 277,332 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 5,642 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 47,052 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 367,362 | 376,458 | 349,152 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 12,290 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 92,867 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 825,176 | 882,968 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 42,188 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 663,914 |  |  |  |  |  |  |  |  |
Insurance | Property and other | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 712,082 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 187,391 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 730,832 |  |  |  |  |  |  |  |  |
Insurance | Marine |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 920,554 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 50,735 | 52,283 | 52,400 | 53,514 | 54,906 | 57,106 | 64,477 | 69,862 | 74,181 | 80,615
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 359 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,220 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 45,125 | 45,543 | 47,249 | 48,650 | 51,483 | 53,388 | 66,389 | 70,394 | 68,528 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 643 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,196 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 68,829 | 68,140 | 65,983 | 65,769 | 65,766 | 72,530 | 78,700 | 90,717 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 1,005 |  |  |  |  |  |  |  |  |
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 | $ 72,585 | 74,445 | 71,823 | 70,855 | 68,715 | 82,648 | 89,639 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 12,055 |  |  |  |  |  |  |  |  |
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 | $ 82,136 | 82,547 | 97,265 | 96,210 | 100,767 | 79,610 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 2,729 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,351 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 45,980 | 44,392 | 48,481 | 44,463 | 59,558 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 5,454 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,157 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 129,627 | 136,827 | 140,050 | 158,755 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 8,498 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,219 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 76,743 | 78,779 | 86,264 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 12,819 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,795 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 170,085 | 171,936 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 49,990 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,863 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 178,709 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 113,414 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,250 |  |  |  |  |  |  |  |  |
Insurance | Aviation |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 261,202 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 13,821 | 14,330 | 14,604 | 15,437 | 16,618 | 16,743 | 18,090 | 18,752 | 14,560 | 17,468
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 41 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,659 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 8,900 | 8,548 | 8,744 | 8,699 | 8,769 | 9,749 | 11,422 | 11,699 | 12,922 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 78 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,950 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 7,203 | 7,242 | 7,275 | 8,422 | 9,552 | 12,779 | 15,390 | 17,723 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 205 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,145 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 7,695 | 7,804 | 7,758 | 8,708 | 10,791 | 10,668 | 12,789 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 200 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,242 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 15,502 | 15,618 | 15,243 | 15,199 | 16,327 | 15,651 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 292 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,320 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 22,183 | 22,104 | 24,339 | 23,028 | 20,432 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 425 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,717 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 30,135 | 30,363 | 28,479 | 29,761 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 1,480 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,484 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 34,513 | 34,328 | 29,154 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 2,845 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,456 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 63,295 | 56,565 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 7,676 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,452 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 57,955 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 12,452 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,280 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 700,799 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 340,648 | 339,534 | 339,570 | 335,291 | 335,271 | 334,965 | 335,536 | 326,024 | 305,282 | 248,083
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 3,600 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 24 |  |  |  |  |  |  |  |  |
Insurance | Credit and political risk | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 99,416 | 90,880 | 72,101 | 65,011 | 64,977 | 65,596 | 63,259 | 63,179 | 62,415 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 1,316 |  |  |  |  |  |  |  |  |
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 | $ 27,899 | 33,604 | 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 | $ 197 | 44 | 10,320 | 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 | $ 14,065 | 14,941 | 9,880 | 9,759 | 25,684 | 26,439 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 5,759 |  |  |  |  |  |  |  |  |
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 | $ 69,586 | 68,320 | 67,109 | 70,712 | 38,825 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 1,136 |  |  |  |  |  |  |  |  |
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 | $ 26,001 | 27,513 | 30,368 | 30,329 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 2,703 |  |  |  |  |  |  |  |  |
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 | $ 42,184 | 44,639 | 45,907 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 17,704 |  |  |  |  |  |  |  |  |
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 | $ 34,631 | 36,563 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 28,083 |  |  |  |  |  |  |  |  |
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 | $ 46,172 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 33,079 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1 |  |  |  |  |  |  |  |  |
Insurance | Professional lines |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 3,298,346 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 224,778 | 220,524 | 212,994 | 236,751 | 236,657 | 253,979 | 244,466 | 243,978 | 243,522 | 240,092
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 13,640 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 5,889 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 186,340 | 167,038 | 179,517 | 157,921 | 181,917 | 204,744 | 233,407 | 235,610 | 230,353 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 18,897 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 5,690 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 351,747 | 351,247 | 342,598 | 329,318 | 324,739 | 331,800 | 314,466 | 312,805 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 33,877 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 7,215 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 351,498 | 362,606 | 360,596 | 373,306 | 374,315 | 372,782 | 327,590 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 50,067 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 8,300 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 353,112 | 351,330 | 361,785 | 394,461 | 394,548 | 382,270 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 70,914 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 9,409 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 369,129 | 389,610 | 418,164 | 407,688 | 408,103 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 111,975 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 9,766 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 355,300 | 380,265 | 373,747 | 374,209 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 127,537 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 10,379 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 355,601 | 349,223 | 346,289 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 152,080 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 11,632 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 393,443 | 375,397 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 256,260 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 12,903 |  |  |  |  |  |  |  |  |
Insurance | Professional lines | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 357,398 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 304,926 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 12,392 |  |  |  |  |  |  |  |  |
Insurance | Liability |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 1,208,108 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 97,964 | 98,999 | 98,384 | 101,179 | 83,281 | 75,883 | 67,869 | 67,410 | 64,017 | 61,469
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 9,450 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,093 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 103,906 | 104,258 | 105,119 | 98,061 | 99,570 | 98,112 | 98,635 | 94,220 | 79,407 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 11,742 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,670 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 82,625 | 82,127 | 83,730 | 85,242 | 87,059 | 83,118 | 75,329 | 72,586 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 17,357 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,222 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 72,514 | 75,341 | 68,180 | 70,770 | 73,281 | 70,631 | 70,861 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 23,236 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,837 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 95,632 | 93,216 | 87,498 | 94,253 | 94,178 | 92,150 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 21,345 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,520 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 131,539 | 130,021 | 128,524 | 122,643 | 106,148 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 31,126 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,614 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 164,036 | 136,305 | 125,819 | 127,319 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 52,818 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 5,975 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 128,172 | 129,139 | 123,243 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 73,747 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 6,628 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 165,061 | 161,211 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 107,070 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 5,842 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 166,659 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 141,099 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,725 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | $ 6,321,728 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 198,189 | 197,779 | 200,422 | 198,498 | 204,560 | 223,245 | 232,639 | 246,047 | 284,210 | 340,527
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 1,722 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 568,179 | 569,043 | 571,120 | 579,065 | 585,247 | 582,855 | 569,357 | 600,219 | 612,614 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 5,532 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,040,130 | 1,038,726 | 1,040,470 | 1,066,384 | 1,083,492 | 1,124,792 | 1,116,708 | 1,109,682 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 10,579 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 457,703 | 456,334 | 461,255 | 477,145 | 507,750 | 523,310 | 555,241 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 8,446 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 502,642 | 503,203 | 509,179 | 529,463 | 560,227 | 578,645 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 5,140 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 519,967 | 521,797 | 534,229 | 560,478 | 540,406 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 43,358 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 453,628 | 459,017 | 463,996 | 477,608 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 14,117 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 620,702 | 633,597 | 614,940 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 30,481 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,080,319 | 1,076,458 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 123,562 |  |  |  |  |  |  |  |  |
Reinsurance | Property and other | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 880,269 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 492,589 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,903,167 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 179,945 | 180,862 | 189,991 | 193,803 | 208,693 | 208,338 | 218,469 | 215,827 | 211,191 | 211,420
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 4,495 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 165,864 | 179,604 | 189,263 | 196,770 | 214,161 | 214,439 | 211,409 | 210,238 | 210,016 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 10,034 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 177,163 | 200,168 | 207,946 | 208,828 | 211,459 | 202,815 | 201,735 | 201,457 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 22,132 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 213,850 | 212,485 | 222,499 | 223,813 | 221,808 | 216,415 | 209,889 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 33,873 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 205,586 | 213,142 | 213,765 | 215,544 | 214,624 | 209,538 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 67,043 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 233,427 | 219,109 | 219,286 | 219,332 | 219,378 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 48,605 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 225,003 | 214,310 | 212,150 | 212,030 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 84,299 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 199,879 | 196,246 | 195,061 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 84,621 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 155,892 | 155,211 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 109,070 |  |  |  |  |  |  |  |  |
Reinsurance | Professional lines | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 146,558 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 142,282 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,201,632 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 92,519 | 93,688 | 95,321 | 95,726 | 98,958 | 104,236 | 105,062 | 105,827 | 122,111 | 143,398
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 1,304 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 74,430 | 75,716 | 77,732 | 79,047 | 86,528 | 90,657 | 93,548 | 100,047 | 119,152 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 4,092 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 100,146 | 100,718 | 102,529 | 111,019 | 112,964 | 105,955 | 107,811 | 121,471 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 5,770 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 128,323 | 131,963 | 140,000 | 148,363 | 151,141 | 148,566 | 160,109 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 8,830 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 125,112 | 136,402 | 140,589 | 144,472 | 153,616 | 165,413 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 8,083 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 128,404 | 139,857 | 143,515 | 136,346 | 135,732 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 11,280 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 157,612 | 161,789 | 166,951 | 160,837 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 26,891 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 149,054 | 141,780 | 142,245 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 38,746 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 134,063 | 135,750 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 38,299 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and surety | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 111,969 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 53,762 |  |  |  |  |  |  |  |  |
Reinsurance | Motor |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 1,942,568 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 77,829 | 80,204 | 77,943 | 83,517 | 92,158 | 90,860 | 89,057 | 87,140 | 79,515 | 81,369
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 17,628 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 78,575 | 81,228 | 84,535 | 93,919 | 99,061 | 104,993 | 106,092 | 105,669 | 98,704 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 19,993 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 140,191 | 145,482 | 155,948 | 164,559 | 168,436 | 162,586 | 158,750 | 156,069 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 24,417 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 131,690 | 134,768 | 144,164 | 149,100 | 156,460 | 167,788 | 178,052 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 22,562 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 131,081 | 134,200 | 137,695 | 147,139 | 158,632 | 162,681 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 21,880 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 169,776 | 174,457 | 177,575 | 182,555 | 182,625 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 9,307 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 221,982 | 220,527 | 216,808 | 222,768 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 29,755 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 263,168 | 261,369 | 245,899 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 43,569 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 371,089 | 363,651 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 84,007 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 357,187 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 172,384 |  |  |  |  |  |  |  |  |
Reinsurance | Liability |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 2,070,199 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 175,770 | 168,917 | 178,260 | 192,287 | 204,531 | 184,811 | 178,149 | 180,945 | 174,121 | $ 172,680
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 13,563 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 159,156 | 165,990 | 181,938 | 190,959 | 201,329 | 183,056 | 182,515 | 170,784 | $ 171,634 |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 14,137 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 191,962 | 193,830 | 194,715 | 197,871 | 191,761 | 174,124 | 172,399 | $ 172,431 |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 24,450 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 164,357 | 171,121 | 173,645 | 172,491 | 167,887 | 163,625 | $ 167,290 |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 27,789 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 177,273 | 184,147 | 184,467 | 182,428 | 176,465 | $ 172,784 |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 53,822 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 199,583 | 200,819 | 204,871 | 203,136 | $ 200,203 |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 75,626 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 215,997 | 216,201 | 215,273 | $ 214,942 |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 97,353 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 251,087 | 246,024 | $ 240,411 |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 131,475 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 270,564 | $ 277,034 |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | 176,854 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and allocated claim adjustment expenses, net of reinsurance | 264,450 |  |  |  |  |  |  |  |  |
Total of incurred-but-not-reported liabilities plus expected development on reported claims | $ 209,612 |  |  |  |  |  |  |  |  |

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