Stockholders' Equity - Summarizes Fortress warrant activities (Detail) - Warrant [Member] - USD ($) |
3 Months Ended | 12 Months Ended |
|---|---|---|
Mar. 31, 2019 |
Dec. 31, 2018 |
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| Subsidiary or Equity Method Investee [Line Items] | ||
| Number of shares, Outstanding | 2,754,189 | |
| Number of shares, Granted | 0 | |
| Number of shares, Forfeited | 0 | |
| Number of shares, Outstanding | 2,754,189 | 2,754,189 |
| Number of shares, Exercisable | 849,189 | |
| Weighted average exercise price, Outstanding | $ 3.28 | |
| Weighted average exercise price, Granted | 0 | |
| Weighted average exercise price, Forfeited | 0 | |
| Weighted average exercise price, Outstanding | 3.28 | $ 3.28 |
| Weighted average exercise price, Exercisable | $ 3.92 | |
| Total weighted average instrinsic value, Outstanding | $ 24,600 | $ 0 |
| Total weighted average intrinsic value, Exercisable | $ 24,600 | |
| Weighted average remaining contractual life (years), Outstanding | 3 years 3 months | 3 years 5 months 26 days |
| Weighted average remaining contractual life, Exercisable (years) | 2 years 10 months 20 days |
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- Definition Weighted average exercise price of shares other than option outstanding. No definition available.
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- Definition Weighted average intrinsic value of shares other than option outstanding exercisable. No definition available.
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- Definition The number of shares into which fully or partially vested other than options outstanding as of the balance sheet date . No definition available.
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- Definition Weighted average exercise price of shares other than option outstanding exercisable. No definition available.
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- Definition Weighted average remaining contractual life of shares other than option outstanding exercisable. No definition available.
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- Definition Weighted average exercise price of shares granted other than option during the period. No definition available.
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- Definition Number of warrants or rights outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options. 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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