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Loss and Loss Adjustment Expenses - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Unpaid Losses And Loss Expenses [Line Items] |  |  |
Loss and LAE Related to Prior Periods | $ (47,814) | $ (23,717) | $ (12,611)
Accident Year 2012 [Member] |  |  |
Unpaid Losses And Loss Expenses [Line Items] |  |  |
Loss and LAE Related to Prior Periods | 19,200 |  |
Accident Year 2013 [Member] |  |  |
Unpaid Losses And Loss Expenses [Line Items] |  |  |
Loss and LAE Related to Prior Periods | 8,200 |  |
Accident Year 2008 [Member] |  |  |
Unpaid Losses And Loss Expenses [Line Items] |  |  |
Loss and LAE Related to Prior Periods | $ 7,200 |  |

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- Definition Unpaid Losses And Loss Expenses [Line Items] + References No definition available. + Details
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- Definition Amount of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Details
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