v3.8.0.1

Segment Information - Net Premiums (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 617,330 | $ 690,653 | $ 2,201,950 | $ 2,133,911
% of Total Net premiums written | 100.00% | 100.00% | 100.00% | 100.00%
Net premiums earned | $ 653,866 | $ 698,278 | $ 2,074,475 | $ 1,951,851
% of Total Net premiums earned | 100.00% | 100.00% | 100.00% | 100.00%
Operating segments [Member] | Diversified Reinsurance segment [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 207,137 | $ 179,092 | $ 671,880 | $ 626,522
% of Total Net premiums written | 33.60% | 25.90% | 30.50% | 29.30%
Net premiums earned | $ 217,513 | $ 175,141 | $ 623,574 | $ 538,152
% of Total Net premiums earned | 33.30% | 25.10% | 30.10% | 27.60%
Operating segments [Member] | AmTrust Reinsurance segment [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 410,193 | $ 511,561 | $ 1,529,980 | $ 1,507,389
% of Total Net premiums written | 66.40% | 74.10% | 69.50% | 70.70%
Net premiums earned | $ 436,353 | $ 523,137 | $ 1,450,811 | $ 1,413,699
% of Total Net premiums earned | 66.70% | 74.90% | 69.90% | 72.40%
Operating segments [Member] | Property [Member] | Diversified Reinsurance segment [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 37,962 | $ 30,606 | $ 132,398 | $ 123,991
% of Total Net premiums written | 6.20% | 4.40% | 6.00% | 5.80%
Net premiums earned | $ 43,362 | $ 29,921 | $ 122,888 | $ 103,023
% of Total Net premiums earned | 6.60% | 4.30% | 5.90% | 5.30%
Operating segments [Member] | Casualty [Member] | Diversified Reinsurance segment [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 129,726 | $ 115,360 | $ 391,503 | $ 365,332
% of Total Net premiums written | 21.00% | 16.70% | 17.80% | 17.10%
Net premiums earned | $ 130,428 | $ 105,893 | $ 375,141 | $ 313,736
% of Total Net premiums earned | 20.00% | 15.20% | 18.10% | 16.10%
Operating segments [Member] | Accident and Health [Member] | Diversified Reinsurance segment [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 16,946 | $ 14,845 | $ 74,504 | $ 68,140
% of Total Net premiums written | 2.70% | 2.20% | 3.40% | 3.20%
Net premiums earned | $ 22,780 | $ 18,436 | $ 63,878 | $ 55,788
% of Total Net premiums earned | 3.50% | 2.60% | 3.10% | 2.80%
Operating segments [Member] | International [Member] | Diversified Reinsurance segment [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 22,503 | $ 18,281 | $ 73,475 | $ 69,059
% of Total Net premiums written | 3.70% | 2.60% | 3.30% | 3.20%
Net premiums earned | $ 20,943 | $ 20,891 | $ 61,667 | $ 65,605
% of Total Net premiums earned | 3.20% | 3.00% | 3.00% | 3.40%
Operating segments [Member] | Small Commercial Business [Member] | AmTrust Reinsurance segment [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 295,499 | $ 314,677 | $ 1,028,905 | $ 983,601
% of Total Net premiums written | 47.90% | 45.60% | 46.70% | 46.10%
Net premiums earned | $ 314,773 | $ 320,596 | $ 946,782 | $ 864,699
% of Total Net premiums earned | 48.10% | 45.90% | 45.60% | 44.30%
Operating segments [Member] | Specialty Program [Member] | AmTrust Reinsurance segment [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 63,816 | $ 98,895 | $ 255,767 | $ 268,193
% of Total Net premiums written | 10.30% | 14.30% | 11.60% | 12.60%
Net premiums earned | $ 59,143 | $ 89,856 | $ 251,153 | $ 251,543
% of Total Net premiums earned | 9.10% | 12.90% | 12.10% | 12.90%
Operating segments [Member] | Specialty Risk and Extended Warranty [Member] | AmTrust Reinsurance segment [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 50,878 | $ 97,989 | $ 245,308 | $ 255,595
% of Total Net premiums written | 8.20% | 14.20% | 11.20% | 12.00%
Net premiums earned | $ 62,437 | $ 112,685 | $ 252,876 | $ 297,457
% of Total Net premiums earned | 9.50% | 16.10% | 12.20% | 15.20%
Other [Member] |  |  |  |
Segment Reporting, Revenue Reconciling Item [Line Items] |  |  |  |
Net premiums written | $ 0 | $ 0 | $ 90 | $ 0
% of Total Net premiums written |  |  | 0.00% | 0.00%
Net premiums earned | $ 0 | $ 0 | $ 90 | $ 0
% of Total Net premiums earned |  |  | 0.00% | 0.00%

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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.1) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(c)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915 + Details
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