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Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2018

Employee Stock Option [Member]

Summary of share option activities

		Number of Option Shares				Weighted Average Grant Date Fair Value				Weighted Average Exercise Price			Weighted Average Remaining Contractual Term
Outstanding at December 31, 2017			2,045,616			$	0.66			$	2.46		7.57 years
Granted			500,000				2.26				5.31
Exercised			(57,222	)			0.47				1.09
Expired			(2,575	)			0.55				3.00
Forfeited			(72,192	)			0.54				3.00
Outstanding at March 31, 2018			2,413,627				1.00				3.06		7.86 years
Vested and exercisable at March 31, 2018			1,120,598

Summary of assumptions used to determine fair value of share options granted

		March 31, 2018
Fair value of common share(1)		$	5.31
Expected term in years(2)			6.25
Volatility(3)			39.14	%
Risk-free interest rate(4)			2.55	%
Expected dividend(5)			0.00	%

Non Employee Awards [Member]

Summary of share option activities

Number of Option Shares

Weighted Average Grant Date Fair Value

Weighted Average Exercise Price

Weighted Average Remaining Contractual Term

Outstanding at December 31, 2017

1,326,676

$

0.78

$

2.52

7.54 years

Granted

─

─

─

─

Exercised

─

─

─

─

Expired

─

─

─

─

Forfeited

─

─

─

─

Outstanding at March 31, 2018

1,326,676

$

0.75

2.52

7.29 years

Vested and exercisable at March 31, 2018

841,329

Summary of assumptions used to determine fair value of share options granted

	March 31, 2018
Fair value of common share(1)	$12.30
Expected term in years(2)	3.33-5.36
Volatility(3)	45.48%
Risk-free interest rate(4)	2.39%-2.56%
Expected dividend(5)	0.00%

X

- Definition

Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value.

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

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

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

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X

- Definition

Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.

+ 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 (f)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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