| Income Taxes - Components of provision for income taxes (Details 1) - USD ($) $ in Thousands | 12 Months Ended | ||
|---|---|---|---|
| Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | |
| Current: | |||
| United States | $ (8,736) | $ (4,621) | $ 9,162 | 
| Total current | (10,902) | (5,503) | 5,884 | 
| Deferred: | |||
| United States | 3,684 | (1,269) | (3,617) | 
| Total deferred: | 3,684 | (1,269) | (3,617) | 
| Income tax benefit (expense) | (7,218) | (6,772) | 2,267 | 
| BERMUDA | |||
| Current: | |||
| Foreign | |||
| Deferred: | |||
| Foreign | |||
| Foreign - Other | |||
| Current: | |||
| Foreign | (2,166) | (882) | (3,278) | 
| Deferred: | |||
| Foreign | |||
| X | ||||||||||
| 
- Definition Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
 | 
| X | ||||||||||
| 
- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
 | 
| X | ||||||||||
| 
- References No definition available. 
 | 
| X | ||||||||||
| 
- Definition Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
 | 
| X | ||||||||||
| 
- Definition Amount of deferred foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
 | 
| X | ||||||||||
| 
- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
 | 
| X | ||||||||||
| 
- References No definition available. 
 | 
| X | ||||||||||
| 
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
 | 
| X | ||||||||||
| 
- Details 
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| X | ||||||||||
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- Details 
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