v3.3.1.900

Commitments, Contingencies and Concentrations (Details) $ / shares in Units, $ in Thousands |  | 12 Months Ended
--- | --- | ---
Nov. 04, 2015 $ / shares | Dec. 31, 2015 USD ($) broker $ / shares | Dec. 31, 2014 USD ($) $ / shares | Dec. 31, 2013 USD ($) $ / shares
Loss Contingencies [Line Items] |  |  |  |
Gross premiums written |  | $ 2,662,825 | $ 2,507,352 | $ 2,204,159
Letters of credit outstanding |  | $ 76,964 | 82,489 |
Renewal term (in years) |  | 5 years |  |
Rent expense |  | $ 1,984 | $ 2,220 | $ 2,171
2016 |  | 1,395 |  |
2017 |  | 1,126 |  |
2018 |  | 534 |  |
2019 |  | 491 |  |
2020 |  | 345 |  |
Total |  | $ 3,891 |  |
Dividends declared per common share (in dollars per share) | $ / shares | $ 0.14 | $ 0.53 | $ 0.46 | $ 0.38
Letter of credit |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Collateral |  | $ 108,666 | $ 115,151 |
AmTrust Reinsurance |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Gross premiums written |  | 1,885,974 | 1,610,485 | $ 1,169,961
Diversified Reinsurance |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Gross premiums written |  | $ 776,852 | $ 897,748 | $ 848,790
Segment concentration risk | Gross premiums written | AmTrust Reinsurance |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Concentration risk, percentage |  | 70.80% | 64.20% | 53.10%
Broker concentration risk | Gross premiums written | Diversified Reinsurance |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Concentration risk, percentage |  | 54.60% | 57.10% | 57.70%
Number of major brokers | broker |  | 3 |  |
Broker concentration risk | Gross premiums written | Diversified Reinsurance | Top 3 Brokers |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Concentration risk, percentage |  | 36.90% | 31.60% | 29.90%
Broker concentration risk | Gross premiums written | Diversified Reinsurance | Aon Benfield Group, Ltd. |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Concentration risk, percentage |  | 17.30% | 15.80% | 11.90%
Broker concentration risk | Gross premiums written | Diversified Reinsurance | Marsh & McLennan Inc. |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Concentration risk, percentage |  | 12.20% | 12.00% | 12.60%
Broker concentration risk | Gross premiums written | Diversified Reinsurance | U.S. RE Corporation |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Concentration risk, percentage |  | 7.40% |  |
Broker concentration risk | Gross premiums written | Diversified Reinsurance | Tiger Risk Partners |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Concentration risk, percentage |  |  | 3.80% |
Broker concentration risk | Gross premiums written | Diversified Reinsurance | Beach & Associates, Ltd. |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Concentration risk, percentage |  |  |  | 5.40%
Investments in limited partnerships |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Unfunded commitment on investments in limited partnerships |  | $ 622 | $ 736 |

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