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
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-Subparagraph (SAB Topic 14.F)
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

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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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Stock-Based Compensation - Service Based Restricted Stock Units (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019
Weighted Average Grant Date Fair Value
Stock based compensation expenses	$ 1,517,302	$ 446,003
Restricted stock units - Service based awards
Number of Shares
Outstanding at beginning of period (in shares)	472,959
Granted (in shares)		0
Outstanding at end of period (in shares)	472,959
Weighted Average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 4.32
Unvested, Weighted Average Grant-Date Fair Value	$ 4.32		$ 4.32
Stock based compensation expenses	$ 300,000	$ 0
Granted (in shares)		0
Unrecognized stock-based compensation expenses			$ 1,300,000
Minimum \| Restricted stock units - Service based awards
Weighted Average Grant Date Fair Value
Vesting period	1 year
Maximum \| Restricted stock units - Service based awards
Weighted Average Grant Date Fair Value
Vesting period	3 years