Fair Value Measurements - Reconciliation of Company's Financial Liabilities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3) (Detail) - Warrant Liabilities [Member] - USD ($) |
3 Months Ended | 9 Months Ended | ||
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Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
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| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
| Balance at beginning of period | $ 38,626,579 | $ 9,581,916 | $ 13,549,437 | $ 12,698,980 |
| Issuance of warrants | 12,383,435 | 12,383,435 | ||
| (Decrease) increase in fair value | (3,246,765) | (5,941,144) | 21,830,377 | (9,058,208) |
| Balance at end of period | $ 35,379,814 | $ 16,024,207 | $ 35,379,814 | $ 16,024,207 |
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- Definition Fair value measurement with unobservable inputs reconciliation recurring basis liability issuance of warrants. No definition available.
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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 Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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