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 ($) |
12 Months Ended | ||
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Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | |||
| Balance at beginning of period | $ 6,068,978 | $ 20,781,663 | $ 13,549,437 |
| Issuance of 2020 warrants | 31,391,369 | ||
| Change in fair value | (8,056,258) | (14,712,685) | 7,232,226 |
| Balance at end of period | $ 29,404,089 | $ 6,068,978 | $ 20,781,663 |
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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 in income from liability measured at fair value on recurring basis using unobservable input (level 3). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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