Income Taxes - Reconciliation of the Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($) |
12 Months Ended | |
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Dec. 31, 2017 |
Dec. 31, 2016 |
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| Income Tax Disclosure [Abstract] | ||
| Beginning balance | $ 1,875,337 | $ 1,708,466 |
| Additions based on tax positions related to the current year | 140,313 | 166,871 |
| Additions for the tax positions of prior years | 0 | 0 |
| Reductions for the tax positions of prior years | 0 | 0 |
| Ending balance | $ 2,015,650 | $ 1,875,337 |
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- References No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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