Commitments and Contingencies - Additional Information (Detail) $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($)
Directors [Member]
Purchase Commitment Excluding Longterm Commitment [Line Items]
Insurance coverage deductibles	$ 2.0
Officers [Member]
Purchase Commitment Excluding Longterm Commitment [Line Items]
Insurance coverage deductibles	$ 1.5

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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