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RESERVE FOR LOSSES AND LOSS EXPENSES - Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009 | Dec. 31, 2008
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Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | $ 9,654,715 |  |  |  |  |  |  |  |  |
Aviabel |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 26,830 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 10,626 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 77,405 |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | (33) |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1 |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 97 |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 20 |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 661 |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 425 |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,944 |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 3,291 |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 5,453 |  |  |  |  |  |  |  |  |
Aviabel | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 14,970 |  |  |  |  |  |  |  |  |
Novae |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 139,427 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 102,164 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 1,300,361 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,458 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,147 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 3,197 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 4,332 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 7,352 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 5,878 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 12,370 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 19,349 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 51,065 |  |  |  |  |  |  |  |  |
Novae | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 33,278 |  |  |  |  |  |  |  |  |
Insurance |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 3,331,536 |  |  |  |  |  |  |  |  |
Insurance | Property and Other |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,930,352 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 3,875 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 880,954 |  |  |  |  |  |  |  |  |
Insurance | Property and Other | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 214,663 | $ 215,071 | $ 215,121 | $ 215,628 | $ 213,569 | $ 211,002 | $ 184,038 | $ 172,320 | $ 150,470 | $ 76,558
Insurance | Property and Other | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 77,466 | 77,187 | 76,865 | 74,636 | 73,538 | 72,622 | 68,768 | 60,166 | 31,379 |
Insurance | Property and Other | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 110,763 | 110,709 | 110,934 | 110,785 | 106,593 | 95,747 | 87,059 | 48,624 |  |
Insurance | Property and Other | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 299,248 | 298,559 | 298,766 | 299,567 | 277,260 | 217,578 | 87,525 |  |  |
Insurance | Property and Other | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 379,696 | 374,485 | 366,854 | 343,503 | 278,870 | 107,358 |  |  |  |
Insurance | Property and Other | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 372,338 | 361,209 | 347,531 | 304,207 | 129,157 |  |  |  |  |
Insurance | Property and Other | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 401,482 | 393,868 | 341,023 | 169,961 |  |  |  |  |  |
Insurance | Property and Other | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 317,850 | 281,377 | 123,126 |  |  |  |  |  |  |
Insurance | Property and Other | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 442,007 | 174,455 |  |  |  |  |  |  |  |
Insurance | Property and Other | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 314,839 |  |  |  |  |  |  |  |  |
Insurance | Marine |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 536,047 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 8,213 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 213,390 |  |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 82,344 | 82,339 | 82,259 | 82,128 | 82,043 | 78,313 | 77,203 | 69,114 | 52,697 | 14,357
Insurance | Marine | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 49,060 | 48,712 | 48,430 | 45,896 | 45,286 | 43,243 | 39,699 | 30,364 | 17,431 |
Insurance | Marine | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 43,587 | 47,088 | 46,150 | 45,373 | 42,554 | 33,392 | 28,771 | 18,062 |  |
Insurance | Marine | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 64,750 | 60,523 | 59,816 | 57,972 | 54,874 | 44,168 | 26,417 |  |  |
Insurance | Marine | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 52,833 | 50,448 | 49,631 | 44,858 | 38,560 | 10,730 |  |  |  |
Insurance | Marine | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 66,326 | 63,637 | 55,414 | 44,437 | 19,313 |  |  |  |  |
Insurance | Marine | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 26,977 | 26,831 | 15,277 | 6,363 |  |  |  |  |  |
Insurance | Marine | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 108,071 | 54,845 | 21,467 |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 32,038 | 12,497 |  |  |  |  |  |  |  |
Insurance | Marine | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 10,061 |  |  |  |  |  |  |  |  |
Insurance | Aviation |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 114,861 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 1,611 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 56,400 |  |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 5,519 | 5,526 | 5,269 | 4,663 | 4,487 | 4,216 | 3,666 | 3,084 | 2,063 | 488
Insurance | Aviation | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 13,547 | 13,755 | 14,258 | 14,322 | 13,957 | 12,834 | 7,071 | 3,628 | 2,118 |
Insurance | Aviation | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 8,247 | 8,152 | 7,708 | 7,586 | 6,920 | 6,341 | 4,156 | 1,053 |  |
Insurance | Aviation | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 6,056 | 5,826 | 5,576 | 5,040 | 4,521 | 2,830 | 639 |  |  |
Insurance | Aviation | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 7,070 | 6,836 | 5,958 | 4,159 | 2,868 | 957 |  |  |  |
Insurance | Aviation | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 13,551 | 11,462 | 9,757 | 7,336 | 4,402 |  |  |  |  |
Insurance | Aviation | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 13,914 | 11,706 | 8,033 | 3,989 |  |  |  |  |  |
Insurance | Aviation | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 21,095 | 16,177 | 8,090 |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 19,403 | 10,421 |  |  |  |  |  |  |  |
Insurance | Aviation | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 6,459 |  |  |  |  |  |  |  |  |
Insurance | Credit and Political Risk |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 631,553 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | (1,475) |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 51,469 |  |  |  |  |  |  |  |  |
Insurance | Credit and Political Risk | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 44,161 | 44,410 | 44,410 | 44,410 | 45,379 | 45,379 | 45,638 | 45,625 | 69,217 | 0
Insurance | Credit and Political Risk | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 340,809 | 345,592 | 345,545 | 345,545 | 341,600 | 346,243 | 346,267 | 344,658 | 92,844 |
Insurance | Credit and Political Risk | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 102,200 | 102,158 | 101,952 | 101,790 | 106,769 | 90,729 | 85,418 | 50,000 |  |
Insurance | Credit and Political Risk | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 27,631 | 27,636 | 27,636 | 27,636 | 27,636 | 37,205 | 32,788 |  |  |
Insurance | Credit and Political Risk | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 42 | 40 | 0 | 0 | 0 | 0 |  |  |  |
Insurance | Credit and Political Risk | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 11,768 | 5,216 | 3,726 | 2,235 | 745 |  |  |  |  |
Insurance | Credit and Political Risk | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 57,855 | 61,108 | 39,952 | 1,924 |  |  |  |  |  |
Insurance | Credit and Political Risk | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 23,298 | 23,309 | 0 |  |  |  |  |  |  |
Insurance | Credit and Political Risk | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 23,789 | 0 |  |  |  |  |  |  |  |
Insurance | Credit and Political Risk | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 0 |  |  |  |  |  |  |  |  |
Insurance | Professional Lines |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,741,257 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 30,546 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 1,559,564 |  |  |  |  |  |  |  |  |
Insurance | Professional Lines | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 268,487 | 267,611 | 249,321 | 214,481 | 189,339 | 167,828 | 124,681 | 68,197 | 22,325 | 4,068
Insurance | Professional Lines | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 179,770 | 167,129 | 127,033 | 107,421 | 97,061 | 69,050 | 44,312 | 20,670 | 1,689 |
Insurance | Professional Lines | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 115,204 | 110,156 | 99,554 | 89,051 | 72,840 | 53,738 | 27,880 | 7,857 |  |
Insurance | Professional Lines | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 283,718 | 238,523 | 165,755 | 108,470 | 74,224 | 32,351 | 6,782 |  |  |
Insurance | Professional Lines | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 255,140 | 231,963 | 185,059 | 100,526 | 41,545 | 7,824 |  |  |  |
Insurance | Professional Lines | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 214,534 | 176,899 | 130,342 | 73,334 | 17,739 |  |  |  |  |
Insurance | Professional Lines | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 194,294 | 131,610 | 71,510 | 23,665 |  |  |  |  |  |
Insurance | Professional Lines | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 138,967 | 68,400 | 20,403 |  |  |  |  |  |  |
Insurance | Professional Lines | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 71,619 | 16,010 |  |  |  |  |  |  |  |
Insurance | Professional Lines | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 19,524 |  |  |  |  |  |  |  |  |
Insurance | Liability |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 560,061 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 44,150 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 569,759 |  |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 87,159 | 61,618 | 55,314 | 51,776 | 47,447 | 37,408 | 27,861 | 18,507 | 8,796 | 1,906
Insurance | Liability | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 84,427 | 83,991 | 44,105 | 41,323 | 31,865 | 26,754 | 13,305 | 4,646 | 726 |
Insurance | Liability | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 86,471 | 71,814 | 66,140 | 61,055 | 53,604 | 30,809 | 15,986 | 1,029 |  |
Insurance | Liability | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 60,263 | 54,996 | 46,074 | 38,377 | 20,190 | 10,540 | 2,761 |  |  |
Insurance | Liability | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 42,745 | 37,140 | 30,146 | 15,412 | 5,515 | 1,631 |  |  |  |
Insurance | Liability | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 60,021 | 42,055 | 33,324 | 23,285 | 2,363 |  |  |  |  |
Insurance | Liability | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 71,630 | 49,858 | 18,662 | 1,419 |  |  |  |  |  |
Insurance | Liability | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 39,767 | 22,474 | 5,439 |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 23,335 | 6,332 |  |  |  |  |  |  |  |
Insurance | Liability | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 4,243 |  |  |  |  |  |  |  |  |
Reinsurance |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 4,945,413 |  |  |  |  |  |  |  |  |
Reinsurance | Property and Other |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 4,037,613 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 6,225 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 1,220,069 |  |  |  |  |  |  |  |  |
Reinsurance | Property and Other | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 517,657 | 519,391 | 519,711 | 514,765 | 514,696 | 510,305 | 497,078 | 444,047 | 316,280 | 158,206
Reinsurance | Property and Other | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 193,973 | 197,310 | 195,614 | 192,746 | 193,309 | 182,556 | 164,047 | 132,309 | 57,796 |
Reinsurance | Property and Other | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 551,588 | 546,253 | 521,377 | 491,817 | 444,822 | 412,731 | 318,198 | 119,385 |  |
Reinsurance | Property and Other | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 991,307 | 976,120 | 902,188 | 872,086 | 769,142 | 561,377 | 242,494 |  |  |
Reinsurance | Property and Other | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 351,558 | 341,925 | 327,361 | 305,020 | 231,961 | 93,847 |  |  |  |
Reinsurance | Property and Other | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 374,944 | 365,089 | 336,940 | 223,666 | 55,047 |  |  |  |  |
Reinsurance | Property and Other | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 369,000 | 351,496 | 274,886 | 65,848 |  |  |  |  |  |
Reinsurance | Property and Other | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 282,967 | 190,057 | 48,116 |  |  |  |  |  |  |
Reinsurance | Property and Other | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 231,682 | 78,916 |  |  |  |  |  |  |  |
Reinsurance | Property and Other | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 172,937 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and Surety |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 878,286 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 10,351 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 375,762 |  |  |  |  |  |  |  |  |
Reinsurance | Credit and Surety | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 94,601 | 94,446 | 94,040 | 93,282 | 91,014 | 88,604 | 86,796 | 71,501 | 70,349 | 20,891
Reinsurance | Credit and Surety | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 89,986 | 89,894 | 89,921 | 89,736 | 87,079 | 83,138 | 80,744 | 78,254 | 32,888 |
Reinsurance | Credit and Surety | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 68,294 | 67,252 | 65,722 | 64,455 | 62,586 | 61,983 | 50,148 | 28,387 |  |
Reinsurance | Credit and Surety | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 91,307 | 88,944 | 86,653 | 82,015 | 74,037 | 56,106 | 22,640 |  |  |
Reinsurance | Credit and Surety | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 114,251 | 112,423 | 108,858 | 102,976 | 88,092 | 50,516 |  |  |  |
Reinsurance | Credit and Surety | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 108,839 | 101,104 | 94,347 | 78,976 | 32,708 |  |  |  |  |
Reinsurance | Credit and Surety | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 97,957 | 88,668 | 62,900 | 35,839 |  |  |  |  |  |
Reinsurance | Credit and Surety | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 103,123 | 84,077 | 33,064 |  |  |  |  |  |  |
Reinsurance | Credit and Surety | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 75,170 | 42,348 |  |  |  |  |  |  |  |
Reinsurance | Credit and Surety | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 34,758 |  |  |  |  |  |  |  |  |
Reinsurance | Professional Lines |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 863,782 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 34,882 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 1,119,534 |  |  |  |  |  |  |  |  |
Reinsurance | Professional Lines | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 139,917 | 133,596 | 124,658 | 109,093 | 92,320 | 70,815 | 49,393 | 21,736 | 6,465 | 373
Reinsurance | Professional Lines | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 143,634 | 138,823 | 128,608 | 108,787 | 83,946 | 63,180 | 32,327 | 8,589 | 914 |
Reinsurance | Professional Lines | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 130,837 | 124,158 | 107,534 | 76,931 | 52,187 | 31,269 | 12,037 | 1,759 |  |
Reinsurance | Professional Lines | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 120,076 | 103,309 | 85,052 | 57,402 | 30,326 | 11,829 | 1,506 |  |  |
Reinsurance | Professional Lines | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 107,581 | 86,211 | 53,801 | 29,730 | 10,441 | 780 |  |  |  |
Reinsurance | Professional Lines | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 81,940 | 65,195 | 30,666 | 12,121 | 1,068 |  |  |  |  |
Reinsurance | Professional Lines | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 74,748 | 48,930 | 13,085 | 2,020 |  |  |  |  |  |
Reinsurance | Professional Lines | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 41,610 | 13,507 | 3,134 |  |  |  |  |  |  |
Reinsurance | Professional Lines | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 20,624 | 1,782 |  |  |  |  |  |  |  |
Reinsurance | Professional Lines | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,815 |  |  |  |  |  |  |  |  |
Reinsurance | Motor |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 760,256 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 129,548 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 1,082,423 |  |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 17,657 | 17,231 | 15,570 | 14,897 | 12,088 | 9,491 | 7,910 | 6,625 | 6,371 | 3,093
Reinsurance | Motor | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 30,378 | 27,248 | 22,446 | 20,029 | 13,627 | 10,020 | 8,428 | 7,134 | 2,819 |
Reinsurance | Motor | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 35,444 | 34,342 | 30,942 | 26,489 | 22,873 | 19,189 | 13,316 | 7,406 |  |
Reinsurance | Motor | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 90,871 | 85,995 | 79,729 | 72,663 | 61,691 | 46,277 | 21,274 |  |  |
Reinsurance | Motor | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 91,896 | 87,658 | 80,891 | 70,634 | 55,282 | 29,727 |  |  |  |
Reinsurance | Motor | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 87,407 | 81,419 | 70,849 | 56,009 | 34,607 |  |  |  |  |
Reinsurance | Motor | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 107,090 | 98,483 | 77,736 | 44,225 |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 118,902 | 97,495 | 58,884 |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 109,559 | 61,938 |  |  |  |  |  |  |  |
Reinsurance | Motor | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 71,052 |  |  |  |  |  |  |  |  |
Reinsurance | Liability |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 807,122 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2008, net of reinsurance | 42,182 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 1,147,625 |  |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 63,903 | 58,022 | 53,882 | 51,922 | 43,509 | 36,567 | 30,028 | 21,953 | 9,952 | $ 2,160
Reinsurance | Liability | Accident Year 2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 135,031 | 129,644 | 125,329 | 105,410 | 73,521 | 56,730 | 44,552 | 17,104 | $ 1,705 |
Reinsurance | Liability | Accident Year 2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 119,872 | 108,938 | 97,617 | 83,976 | 62,300 | 46,207 | 17,659 | $ 2,484 |  |
Reinsurance | Liability | Accident Year 2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 123,719 | 112,581 | 92,696 | 70,283 | 40,021 | 21,297 | $ 5,191 |  |  |
Reinsurance | Liability | Accident Year 2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 101,343 | 78,368 | 58,855 | 28,418 | 12,809 | $ 3,542 |  |  |  |
Reinsurance | Liability | Accident Year 2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 88,327 | 69,098 | 52,360 | 22,259 | $ 5,978 |  |  |  |  |
Reinsurance | Liability | Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 70,389 | 48,498 | 28,699 | $ 7,117 |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 54,646 | 27,473 | $ 7,273 |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 37,819 | $ 11,891 |  |  |  |  |  |  |  |
Reinsurance | Liability | Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 12,073 |  |  |  |  |  |  |  |  |

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