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RESERVE FOR LOSSES AND LOSS EXPENSES (DETAILS 5) $ in Thousands | Dec. 31, 2016 USD ($) claim | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($) | Dec. 31, 2012 USD ($) | Dec. 31, 2011 USD ($) | Dec. 31, 2010 USD ($) | Dec. 31, 2009 USD ($) | Dec. 31, 2008 USD ($) | Dec. 31, 2007 USD ($)
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Insurance [Member] | Property and Other Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 3,033,236 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 519,834 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 189,742 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 51,460 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 375,867 | $ 378,216 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 38,959 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 43,312 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 442,392 | 467,335 | $ 471,402 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 19,696 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 60,120 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 381,573 | 387,086 | 414,793 | $ 421,113 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 10,120 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 51,231 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 422,394 | 426,457 | 446,790 | 470,059 | $ 463,117 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 9,381 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 27,679 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 315,517 | 316,756 | 317,110 | 340,974 | 364,736 | $ 386,326 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 2,583 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3,736 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 115,888 | 116,193 | 117,130 | 122,700 | 147,867 | 155,368 | $ 182,337 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 469 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 2,309 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 80,880 | 81,204 | 80,983 | 83,139 | 85,202 | 92,505 | 101,823 | $ 120,169 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 815 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1,483 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 231,713 | 232,738 | 234,488 | 238,882 | 240,324 | 255,880 | 265,330 | 273,666 | $ 318,702 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 2,017 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1,573 |  |  |  |  |  |  |  |  |
Insurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 147,178 | 147,552 | 147,875 | 148,350 | 149,580 | 149,236 | 151,107 | 160,343 | 162,796 | $ 209,411
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 449 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 834 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 781,666 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 86,115 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 41,293 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 804 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 138,915 | 158,240 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 23,853 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 850 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 47,870 | 44,221 | 59,880 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 8,864 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 794 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 95,954 | 94,917 | 99,885 | 79,011 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 9,907 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 727 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 71,370 | 70,404 | 68,315 | 82,344 | 89,663 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 9,821 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 697 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 65,572 | 65,363 | 65,383 | 72,137 | 78,293 | 90,608 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 2,449 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 602 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 45,934 | 47,397 | 50,248 | 52,161 | 65,198 | 69,312 | 67,916 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ (1,368) |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 472 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 53,652 | 54,774 | 56,208 | 58,383 | 65,787 | 71,049 | 75,532 | 82,075 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 531 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 475 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 84,221 | 84,483 | 84,848 | 88,612 | 95,006 | 102,201 | 103,287 | 108,208 | 107,697 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 324 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 516 |  |  |  |  |  |  |  |  |
Insurance [Member] | Marine Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 92,063 | 92,077 | 92,405 | 94,612 | 96,304 | 97,949 | 100,962 | 106,228 | 95,994 | 96,533
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 257 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 684 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 153,462 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 29,135 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 9,919 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1,143 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 28,453 | 29,748 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 4,999 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1,751 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 24,322 | 23,016 | 20,429 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 2,969 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1,255 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 15,223 | 15,179 | 16,313 | 15,647 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 1,010 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1,005 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 7,728 | 8,678 | 10,764 | 10,642 | 12,772 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 499 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 866 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 7,257 | 8,404 | 9,536 | 12,763 | 15,377 | 17,721 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 434 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 730 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 8,418 | 8,370 | 8,444 | 9,419 | 11,095 | 11,383 | 12,629 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 253 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 516 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 14,519 | 15,351 | 16,535 | 16,835 | 18,007 | 18,680 | 14,490 | 17,408 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 176 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 317 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 5,985 | 5,840 | 5,925 | 7,095 | 8,243 | 8,341 | 8,504 | 12,009 | 14,480 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 91 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 187 |  |  |  |  |  |  |  |  |
Insurance [Member] | Aviation Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 12,422 | 12,853 | 12,958 | 14,427 | 16,352 | 16,756 | 17,043 | 22,682 | 25,466 | 29,801
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 53 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 270 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 665,275 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 43,756 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 19,043 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 30,368 | 30,329 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 7,059 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 67,109 | 70,712 | 38,825 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 9,247 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 5 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 9,880 | 9,759 | 25,684 | 26,439 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 1,600 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 10,319 | 12,447 | 12,435 | 15,672 | 32,602 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 10,282 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 4 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 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 | $ 17,400 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 4 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 72,099 | 65,009 | 64,975 | 65,595 | 63,259 | 63,179 | 62,415 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 6,900 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 6 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 339,557 | 335,278 | 335,258 | 335,398 | 335,525 | 326,017 | 305,277 | 248,082 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 1,740 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 24 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 44,410 | 45,200 | 45,600 | 45,551 | 45,551 | 45,554 | 48,715 | 63,552 | 52,993 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 9 |  |  |  |  |  |  |  |  |
Insurance [Member] | Credit and Political Risk Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,741 | 3,667 | 3,642 | 3,609 | 898 | 898 | 5,253 | 16,695 | 44,972 | 50,812
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 200 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 2 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 3,307,104 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 348,076 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 312,698 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 8,935 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 401,660 | 401,941 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 277,836 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 10,178 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 451,917 | 443,665 | 435,447 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 244,910 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 10,017 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 398,776 | 430,517 | 425,400 | 410,537 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 161,370 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 9,835 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 397,517 | 408,870 | 401,976 | 399,610 | 353,693 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 108,180 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 8,805 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 368,830 | 355,008 | 348,860 | 359,448 | 342,063 | 341,302 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 69,175 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 7,633 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 195,869 | 173,104 | 195,831 | 218,436 | 255,337 | 257,527 | 251,985 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 44,799 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 5,975 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 223,700 | 247,495 | 245,939 | 263,157 | 256,731 | 258,134 | 257,354 | 251,995 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 14,856 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 6,148 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 324,197 | 326,623 | 328,628 | 309,268 | 295,953 | 299,422 | 280,329 | 279,486 | 240,809 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 23,024 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 4,582 |  |  |  |  |  |  |  |  |
Insurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 196,562 | 197,765 | 202,636 | 201,294 | 217,901 | 221,708 | 248,741 | 249,780 | 247,155 | 221,212
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 4,683 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3,596 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 1,025,716 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 123,233 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 107,850 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3,099 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 125,844 | 127,318 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 83,145 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 2,970 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 128,465 | 122,583 | 106,121 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 55,811 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 2,240 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 87,491 | 94,247 | 94,171 | 92,146 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 36,011 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1,494 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 68,179 | 70,769 | 73,280 | 70,608 | 70,836 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 23,448 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1,215 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 83,730 | 85,243 | 87,059 | 83,118 | 75,329 | 72,586 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 20,189 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 1,776 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 105,123 | 98,064 | 99,574 | 98,115 | 98,637 | 94,222 | 79,406 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 15,988 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 2,196 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 98,384 | 101,179 | 83,281 | 76,431 | 67,869 | 67,410 | 64,017 | 61,469 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 11,813 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 2,735 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 108,189 | 102,444 | 101,589 | 81,949 | 82,225 | 81,785 | 80,947 | 79,836 | 82,969 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 20,340 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3,697 |  |  |  |  |  |  |  |  |
Insurance [Member] | Liability Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 97,078 | 97,526 | 101,299 | 102,010 | 99,483 | 98,851 | 98,625 | 95,435 | 88,102 | 100,380
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 12,107 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3,766 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 4,518,583 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 440,384 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 224,911 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 359,185 | 380,660 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 69,223 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 442,330 | 455,607 | 437,470 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 53,805 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 392,459 | 411,440 | 441,492 | 466,295 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 10,724 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 393,775 | 409,836 | 440,303 | 450,563 | 484,438 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 10,707 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,006,528 | 1,032,549 | 1,049,625 | 1,090,593 | 1,092,015 | 1,083,060 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 10,715 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 555,647 | 563,532 | 569,697 | 567,341 | 553,798 | 584,912 | 599,084 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 7,034 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 195,545 | 193,703 | 199,777 | 220,889 | 227,777 | 241,346 | 279,833 | 337,333 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 705 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 512,261 | 513,948 | 520,174 | 536,555 | 547,586 | 562,028 | 584,076 | 569,031 | 671,079 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | (296) |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Property and Other Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 220,469 | 220,937 | 224,023 | 231,597 | 238,779 | 249,436 | 265,204 | 279,571 | 321,110 | 394,054
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 379 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,108,807 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 138,876 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 72,455 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 161,178 | 156,959 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 46,635 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 139,026 | 131,887 | 132,483 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 34,983 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 136,024 | 139,761 | 148,760 | 161,647 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 23,760 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 134,620 | 142,639 | 145,147 | 142,870 | 155,730 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 19,094 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 96,269 | 104,414 | 106,196 | 99,640 | 101,752 | 117,902 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 9,658 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 71,016 | 72,316 | 79,568 | 83,888 | 86,340 | 92,842 | 112,888 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 6,397 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 90,893 | 91,346 | 94,541 | 99,872 | 100,177 | 100,943 | 117,004 | 137,963 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 2,968 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 87,130 | 87,638 | 88,619 | 92,118 | 93,339 | 92,151 | 92,784 | 102,595 | 79,689 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 1,456 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Credit and Surety Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 53,775 | 52,838 | 53,938 | 45,853 | 39,584 | 39,015 | 40,395 | 44,789 | 53,197 | 48,646
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 915 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,925,942 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 194,558 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 183,486 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 211,181 | 211,420 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 163,900 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 218,610 | 218,662 | 218,734 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 120,754 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 212,763 | 214,659 | 213,810 | 208,804 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 114,919 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 221,722 | 223,023 | 221,036 | 215,586 | 209,109 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 94,535 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 207,237 | 208,126 | 210,770 | 201,989 | 200,776 | 200,400 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 75,492 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 188,729 | 196,067 | 213,316 | 213,560 | 210,413 | 209,034 | 208,718 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 42,307 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 189,290 | 192,974 | 207,939 | 208,234 | 217,656 | 215,065 | 210,413 | 210,606 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 21,035 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 170,596 | 170,509 | 172,414 | 171,409 | 175,203 | 177,038 | 181,097 | 181,729 | 174,881 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 14,293 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Professional Lines Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 111,256 | 114,714 | 118,321 | 137,392 | 151,628 | 176,792 | 196,696 | 204,594 | 204,971 | 195,045
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 8,173 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,291,908 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 238,258 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 100,635 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 207,409 | 215,342 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 49,375 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 168,846 | 173,568 | 175,848 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 33,650 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 130,299 | 139,138 | 150,277 | 155,880 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 30,902 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 137,841 | 142,454 | 149,420 | 159,822 | 170,379 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 37,418 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 148,843 | 156,912 | 160,516 | 155,096 | 151,432 | 149,535 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 44,483 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 77,560 | 86,409 | 91,248 | 96,811 | 97,823 | 97,598 | 92,168 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 27,778 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 73,670 | 78,929 | 87,017 | 85,870 | 83,944 | 82,170 | 75,034 | 77,092 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 17,780 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 54,678 | 58,250 | 63,627 | 67,783 | 68,486 | 70,961 | 68,617 | 69,234 | 64,513 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 18,178 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Motor Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 54,504 | 55,279 | 58,086 | 59,548 | 60,568 | 63,813 | 62,768 | 62,829 | 66,567 | 65,601
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 14,117 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,750,303 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2016 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 238,524 |  |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 199,828 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2015 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 213,776 | 213,387 |  |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 157,257 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2014 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 203,252 | 201,551 | 198,634 |  |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 124,579 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2013 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 182,813 | 180,802 | 174,885 | 171,121 |  |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 83,598 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2012 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 172,176 | 171,033 | 166,492 | 162,127 | 165,409 |  |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 55,572 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2011 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 193,749 | 196,805 | 190,043 | 172,708 | 170,606 | 170,182 |  |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 45,166 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2010 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 180,860 | 189,531 | 199,656 | 181,663 | 180,949 | 168,929 | 169,442 |  |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 53,863 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2009 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 177,852 | 191,701 | 203,553 | 184,378 | 176,853 | 179,239 | 171,868 | 169,886 |  |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 34,578 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2008 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 94,589 | 105,286 | 110,545 | 132,317 | 137,793 | 139,592 | 138,926 | 137,932 | 137,646 |
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | 20,513 |  |  |  |  |  |  |  |  |
Reinsurance [Member] | Liability Reserve Class [Member] | Accident Year 2007 [Member] |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 92,712 | $ 97,515 | $ 114,939 | $ 144,241 | $ 157,822 | $ 157,886 | $ 157,966 | $ 158,773 | $ 157,947 | $ 160,455
Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 11,940 |  |  |  |  |  |  |  |  |

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