Stock-Based Compensation - Performance Based Stock Options (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Weighted Average Exercise Price
Granted (in dollars per share)	$ 2.71
Fair value assumptions:
Stock based compensation expenses	$ 4,387,554	$ 7,174,596
Stock option awards - Performance based awards
Number of Shares
Granted (in shares)	388,125
Outstanding at the end of the period (in shares)	388,125
Weighted Average Exercise Price
Outstanding at the end of the period (in dollars per share)	$ 4.70
Number of shares per unit	1
Fair value assumptions:
Expected stock price volatility	70.00%
Risk-free interest rate	2.90%
Term (years)	10 years
Stock based compensation expenses	$ 160,662
Unrecognized stock-based compensation expenses	$ 900,000
Performance-based
Number of Shares
Granted (in shares)	129,375
Weighted Average Exercise Price
Granted (in dollars per share)	$ 4.70
Number of shares per unit	1
Market-based
Number of Shares
Granted (in shares)	258,750
Weighted Average Exercise Price
Granted (in dollars per share)	$ 4.70

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: 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.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

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- References

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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.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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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
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-Paragraph 2
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