v3.8.0.1

Segment Information - Net Income (Loss) and Total Assets (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) | Sep. 30, 2017 USD ($) Segment | Sep. 30, 2016 USD ($) | Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items] |  |  |  |  |
Number of reporting segments | Segment |  |  | 2 |  |
Net Income (Loss) [Abstract] |  |  |  |  |
Gross premiums written | $ 630,972 | $ 706,854 | $ 2,259,597 | $ 2,259,290 |
Net premiums written | 617,330 | 690,653 | 2,201,950 | 2,133,911 |
Net premiums earned | 653,866 | 698,278 | 2,074,475 | 1,951,851 |
Other insurance revenue | 2,488 | 2,345 | 7,816 | 8,696 |
Net loss and loss adjustment expense (loss and LAE) | (535,968) | (466,751) | (1,545,157) | (1,297,361) |
Commission and other acquisition expenses | (193,462) | (206,706) | (625,530) | (587,501) |
General and administrative expenses | (9,366) | (9,797) | (28,059) | (29,025) |
Underwriting (loss) income | (82,442) | 17,369 | (116,455) | 46,660 |
Reconciliation to net income |  |  |  |  |
Net investment income and realized gains on investment | 46,682 | 37,566 | 131,808 | 111,802 |
Interest and amortization expenses | (4,829) | (6,856) | (18,430) | (21,314) |
Accelerated amortization of senior note issuance cost | 0 | 0 | (2,809) | (2,345) |
Amortization of intangible assets | (533) | (616) | (1,599) | (1,846) |
Foreign exchange gains (losses) | (3,550) | 687 | (12,193) | 6,474 |
Other general and administrative expenses | (10,126) | (7,155) | (24,193) | (20,713) |
Income tax expense | (256) | (199) | (1,017) | (1,206) |
Net (loss) income | $ (55,054) | $ 40,796 | $ (44,888) | $ 117,512 |
Net loss and LAE ratio | 81.60% | 66.60% | 74.20% | 66.20% |
Commission and other acquisition expense ratio | 29.50% | 29.50% | 30.00% | 30.00% |
General and administrative expense ratio | 3.00% | 2.40% | 2.50% | 2.50% |
Expense ratio | 32.50% | 31.90% | 32.50% | 32.50% |
Combined ratio | 114.10% | 98.50% | 106.70% | 98.70% |
Assets [Abstract] |  |  |  |  |
Total assets | $ 6,839,097 |  | $ 6,839,097 |  | $ 6,252,299
AmTrust Reinsurance segment [Member] |  |  |  |  |
Net Income (Loss) [Abstract] |  |  |  |  |
Gross premiums written | 420,019 | $ 520,104 | 1,575,677 | $ 1,591,902 |
Operating segments [Member] |  |  |  |  |
Assets [Abstract] |  |  |  |  |
Total assets - reportable segments | 6,260,044 |  | 6,260,044 |  | 5,687,387
Corporate assets | 579,053 |  | 579,053 |  | 564,912
Total assets | 6,839,097 |  | 6,839,097 |  | 6,252,299
Operating segments [Member] | Diversified Reinsurance segment [Member] |  |  |  |  |
Net Income (Loss) [Abstract] |  |  |  |  |
Gross premiums written | 210,953 | 186,750 | 683,839 | 667,388 |
Net premiums written | 207,137 | 179,092 | 671,880 | 626,522 |
Net premiums earned | 217,513 | 175,141 | 623,574 | 538,152 |
Other insurance revenue | 2,488 | 2,345 | 7,816 | 8,696 |
Net loss and loss adjustment expense (loss and LAE) | (172,273) | (132,396) | (487,759) | (395,718) |
Commission and other acquisition expenses | (54,810) | (39,868) | (159,744) | (139,895) |
General and administrative expenses | (8,595) | (9,038) | (25,819) | (26,717) |
Underwriting (loss) income | $ (15,677) | $ (3,816) | $ (41,932) | $ (15,482) |
Reconciliation to net income |  |  |  |  |
Net loss and LAE ratio | 78.30% | 74.60% | 77.20% | 72.40% |
Commission and other acquisition expense ratio | 24.90% | 22.50% | 25.30% | 25.60% |
General and administrative expense ratio | 3.90% | 5.10% | 4.10% | 4.80% |
Expense ratio | 28.80% | 27.60% | 29.40% | 30.40% |
Combined ratio | 107.10% | 102.20% | 106.60% | 102.80% |
Assets [Abstract] |  |  |  |  |
Total assets - reportable segments | $ 1,898,036 |  | $ 1,898,036 |  | 1,787,320
Corporate assets | 0 |  | 0 |  | 0
Total assets | 1,898,036 |  | 1,898,036 |  | 1,787,320
Operating segments [Member] | AmTrust Reinsurance segment [Member] |  |  |  |  |
Net Income (Loss) [Abstract] |  |  |  |  |
Gross premiums written | 420,019 | $ 520,104 | 1,575,677 | $ 1,591,902 |
Net premiums written | 410,193 | 511,561 | 1,529,980 | 1,507,389 |
Net premiums earned | 436,353 | 523,137 | 1,450,811 | 1,413,699 |
Other insurance revenue | 0 | 0 | 0 | 0 |
Net loss and loss adjustment expense (loss and LAE) | (355,030) | (334,310) | (1,047,222) | (898,703) |
Commission and other acquisition expenses | (138,650) | (166,836) | (465,789) | (447,604) |
General and administrative expenses | (771) | (759) | (2,240) | (2,308) |
Underwriting (loss) income | $ (58,098) | $ 21,232 | $ (64,440) | $ 65,084 |
Reconciliation to net income |  |  |  |  |
Net loss and LAE ratio | 81.40% | 63.90% | 72.20% | 63.50% |
Commission and other acquisition expense ratio | 31.70% | 31.90% | 32.10% | 31.70% |
General and administrative expense ratio | 0.20% | 0.10% | 0.10% | 0.20% |
Expense ratio | 31.90% | 32.00% | 32.20% | 31.90% |
Combined ratio | 113.30% | 95.90% | 104.40% | 95.40% |
Assets [Abstract] |  |  |  |  |
Total assets - reportable segments | $ 4,362,008 |  | $ 4,362,008 |  | 3,900,067
Corporate assets | 0 |  | 0 |  | 0
Total assets | 4,362,008 |  | 4,362,008 |  | $ 3,900,067
Other [Member] |  |  |  |  |
Net Income (Loss) [Abstract] |  |  |  |  |
Gross premiums written | 0 | $ 0 | 81 | $ 0 |
Net premiums written | 0 | 0 | 90 | 0 |
Net premiums earned | 0 | 0 | 90 | 0 |
Other insurance revenue | 0 | 0 | 0 | 0 |
Net loss and loss adjustment expense (loss and LAE) | (8,665) | (45) | (10,176) | (2,940) |
Commission and other acquisition expenses | (2) | (2) | 3 | (2) |
General and administrative expenses | 0 | 0 | 0 | 0 |
Underwriting (loss) income | $ (8,667) | $ (47) | $ (10,083) | $ (2,942) |

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