Significant Accounting Policies - Additional Information (Detail) - USD ($) |
12 Months Ended | ||||
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May 21, 2015 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Apr. 10, 2015 |
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| Summary Of Significant Accounting Policies [Line Items] | |||||
| Research and development expense, total | $ 33,230,668 | $ 32,832,677 | $ 18,825,041 | ||
| Antidilutive securities excluded from computation of earnings per share, amount | 7,324,400 | 6,975,651 | 4,994,425 | ||
| Employee Stock Purchase Plan [Member] | |||||
| Summary Of Significant Accounting Policies [Line Items] | |||||
| Common stock, capital shares reserved for future issuance | 600,000 | ||||
| Common stock purchase price discount percentage | 15.00% | ||||
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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Aggregate number of common shares reserved for future issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Represents the percentage of discount on purchase price of common stock. 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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- Details
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