Income Taxes -Summary of Valuation Allowance (Detail) - USD ($) |
12 Months Ended | |
|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Income Tax Disclosure [Abstract] | ||
| January 1, | $ 39,719,606 | $ 22,085,888 |
| Increase in valuation allowance | 6,452,358 | 17,633,718 |
| December 31, | $ 46,171,964 | $ 39,719,606 |
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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