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Variable Interest Entities (Details) - director | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Jun. 30, 2015
Variable Interest Entity [Line Items] |  |  |
Percentage of par value of policy reinsured | 15.00% |  |
HG Global |  |  |
Variable Interest Entity [Line Items] |  |  |
Percentage of par value of policy reinsured |  | 15.00% |
BAM |  |  |
Variable Interest Entity [Line Items] |  |  |
Right to elect directors on board number | 2 |  |
Prospector Offshore Fund |  |  |
Variable Interest Entity [Line Items] |  |  |
Ownership of variable interest entity |  |  | 67.60%
First Loss Reinsurance Treaty | HG Global |  |  |
Variable Interest Entity [Line Items] |  |  |
Percentage of par value of policy reinsured | 15.00% |  |
First Loss Reinsurance Treaty | BAM |  |  |
Variable Interest Entity [Line Items] |  |  |
Percentage of premiums | 60.00% |  |

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- Definition Percentage of par value of policy reinsured. + References No definition available. + Details
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- Definition Represents the number of directors who can be elected to the board by the holders of the preference shares, subject to certain specified conditions. + References No definition available. + Details
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