Stockholders' Equity - Warrant activities (Details) - $ / shares |
6 Months Ended | 12 Months Ended |
|---|---|---|
Jun. 30, 2019 |
Dec. 31, 2018 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Weighted Average Remaining Contractual Life, Outstanding (in years) | 2 years 11 months 1 day | |
| Warrants | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Warrants, Outstanding as of December 31, 2018 | 5,210,698 | |
| Warrants, Granted | 288,184 | |
| Warrants, Exercised | (65,358) | |
| Warrants, Outstanding as of March 31, 2019 | 5,433,524 | 5,210,698 |
| Weighted Average Exercise Price, Outstanding as of December 31, 2018 | $ 8.32 | |
| Weighted Average Exercise Price, Granted | 3.47 | |
| Weighted Average Exercise Price, Exercised | 0 | |
| Weighted Average Exercise Price, Outstanding as of March 31, 2019 | $ 8.16 | $ 8.32 |
| Weighted Average Remaining Contractual Life, Granted (in years) | 9 years 9 months | |
| Weighted Average Remaining Contractual Life, Outstanding (in years) | 3 years 1 month 6 days |
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- Definition Weighted average per share amount at which grantees can exercise shares of common stock by exercise of equity instruments other than options. No definition available.
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- Definition The number of equity based payment instruments, excluding stock (or unit) options, that exercised during the reporting period. No definition available.
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of equity instruments other than options. No definition available.
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. No definition available.
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- Definition Weighted average remaining contractual term for equity-based awards excluding options No definition available.
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- Definition The number of outstanding equity instruments other then option. No definition available.
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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 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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