Stock Warrants - Additional Information (Detail) - Common Stock Warrant [Member] - shares	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Class of Warrant or Right [Line Items]
Number of warrants cashless exercised	2,295,000	75,000	65,000
Number of common stock issued as a result of cashless exercise of warrants	1,695,000	38,000	35,000

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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