Stock-Based Compensation - Service Based Stock Options - Others (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	$ 4,387,554	$ 7,174,596
Stock option awards - Service based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	1,447,479
Vested options exercisable at an average price	$ 8.03
Unvested options exercisable at an average price	$ 4.54
Allocated Share-based Compensation Expense	$ 1,588,291	$ 3,858,503
Unrecognized stock-based compensation expenses	$ 2,700,000
Chief Executive Officer \| Stock option awards - Service based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated vesting	258,334
Chief Financial Officer \| Stock option awards - Service based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated vesting	71,667
Additional stock-based compensation	$ 162,000

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.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ 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 (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

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- Definition

Net number of share options (or share units) granted during 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 (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Number of shares for which recognition of compensation cost was accelerated.

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Weighted average grant-date fair value of non-vested options outstanding.

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Weighted average grant-date fair value of options vested.

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