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Stockholders' Equity - Schedule of Fair Value of Warrant Valuation Assumptions (Detail) - $ / shares |  | 12 Months Ended
--- | --- | ---
Apr. 14, 2016 | Dec. 31, 2016
Schedule Of Warrant Valuation Assumptions [Line Items] |  |
Price per share of Allenex used to determine fair value of non controlling interest |  | $ 2.70
Private Placement Warrants [Member] |  |
Schedule Of Warrant Valuation Assumptions [Line Items] |  |
Price per share of Allenex used to determine fair value of non controlling interest | $ 4.45 | 2.70
Exercise Price | $ 4.98 | $ 4.00
Remaining term (in years) | 7 years | 6 years 3 months 15 days
Volatility | 46.90% | 51.40%
Risk-free interest rate | 1.57% | 2.14%
Expected dividend yield | 0.00% | 0.00%
Placement Agent Warrants [Member] |  |
Schedule Of Warrant Valuation Assumptions [Line Items] |  |
Price per share of Allenex used to determine fair value of non controlling interest | $ 4.45 | $ 2.70
Exercise Price | $ 3.99 | $ 3.99
Remaining term (in years) | 5 years | 4 years 3 months 15 days
Volatility | 49.00% | 56.10%
Risk-free interest rate | 1.26% | 1.77%
Expected dividend yield | 0.00% | 0.00%

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- Definition Schedule of warrant valuation assumptions. + References No definition available. + Details
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- Definition Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award. + References No definition available. + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 + Details
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