Estimated Earned Premium and Incurred Losses (Detail) - Hiscox Bermuda - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Assumed earned premium	$ 27	$ 2,266	$ 6,383
Assumed losses and loss adjustment expenses	$ (527)	$ 509	$ 763

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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