Refers to the number of years shares will automatically increase.

No definition available.

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- Definition

Refers to the percentage of annual increase which is equal to the company's fully diluted share.

+ References

No definition available.

+ Details

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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- References

No definition available.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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

+ References

+ Details

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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

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- References

No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

+ Details

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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.

+ References

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- Definition

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

+ References

+ Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

+ Details

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Balance Type:	na
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- References

No definition available.

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Data Type:	xbrli:stringItemType
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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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Balance Type:	na
Period Type:	duration

- 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-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.

+ Details

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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
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-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 S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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- Definition

Number of non-vested options forfeited.

+ References

No definition available.

+ Details

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- Definition

Number of options vested.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
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Share-Based Compensation (Stock Options) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2018	Sep. 30, 2016	Apr. 30, 2016	Apr. 30, 2015
Stock Options, Additional Disclosures
Percentage of company's fully diluted shares	20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected stock price volatility	66.50%	65.10%
Expected life of options (years)	5 years 9 months 18 days	6 years 1 month 6 days
Expected dividend yield	0.00%	0.00%
Risk free interest rate	2.50%	2.10%
Unrecognized share-based compensation
Unrecognized share-based compensation cost	$ 8,800,000
Unrecognized share-based compensation - Weighted average period	2 years 3 months 18 days
ESPP
Stock Options, Additional Disclosures
Common stock reserved for issuance (in shares)					150,000
Granted (in shares)	0
2015 Plan \| Employees, directors and consultants
Stock Options, Additional Disclosures
Common stock reserved for issuance (in shares)						320,615
Number of Options
Vested	180,348	136,353
Forfeited, nonvested	3,500	3,250
Available for future issuance	158,906
A&R 2015 Plan
Stock Options, Additional Disclosures
Common stock reserved for issuance (in shares)			415,077
Number of years common shares automatically increase	10 years
Number of Options
Stock options outstanding	2,926,227		2,815,077
A&R 2015 Plan \| Employees, directors and consultants
Stock Options, Additional Disclosures
Common stock reserved for issuance (in shares)					2,400,000
A&R 2015 Plan \| Employees, Directors, Officers, and Consultants
Stock Options, Additional Disclosures
Granted (in shares)	472,000	123,500
Vesting period	4 years
Weighted average fair value per share of options granted	$ 10.18	$ 6.32
Inducement Plan
Stock Options, Additional Disclosures
Common stock reserved for issuance (in shares)				300,000
Restricted stock awards
Unrecognized share-based compensation
Unrecognized share-based compensation cost - RSA	$ 0