Fair Value Measurements - Information about Company's Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) |
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Marketable securities | $ 26,645,137 | $ 39,858,864 |
| Warrant liabilities | (35,379,814) | (13,549,437) |
| Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Cash equivalents | 10,237,703 | 5,949,477 |
| Marketable securities | 26,645,137 | 39,858,864 |
| Total assets (liabilities) | 36,882,840 | 45,808,341 |
| Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Warrant liabilities | 35,379,814 | 13,549,437 |
| Total assets (liabilities) | $ 35,379,814 | $ 13,549,437 |
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. No definition available.
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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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- Definition Fair value of asset after deduction of liability. No definition available.
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- Definition Amount of investment in marketable security, classified as current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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