Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Non-Employee

No definition available.

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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)
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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

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=6415400&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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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
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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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

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-Publisher FASB
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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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- Definition

Period from grant date that an equity-based award expires, 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
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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Stock-based compensation - Narrative (Details) - USD ($)	1 Months Ended			10 Months Ended	12 Months Ended		34 Months Ended
	Aug. 31, 2016	May 31, 2016	Nov. 30, 2015	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Sep. 30, 2014	Apr. 30, 2014	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				$ 1,462,061	$ 6,572,963	$ 6,597,359
Shares granted				1,020,234	763,320	994,748
Shares granted, weighted-average grant date fair value (in usd per share)				$ 2.20	$ 6.35	$ 8.55
Shares exercised				13,572	8,516	47,280
Shares exercised, weighted average exercise price (in usd per share)				$ 0.60	$ 2.59	$ 8.63
Stock options exercised, intrinsic value				$ 51,719	$ 64,302	$ 149,386
Unrecognized compensation cost					$ 8,668,326		$ 8,668,326
Unrecognized compensation cost, recognition period					2 years 1 month 10 days
Non-employee Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted to non-employee consultants and members of the Scientific Advisory Board							272,993
Stock options, vesting period							4 years
Stock options, contractual term							10 years
Stock-based compensation expense				$ 149,000	$ 369,735	$ 517,336
Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, contractual term					10 years
Stock-based compensation expense	$ 58,000	$ 227,000
Options to purchase common stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period					1 year
Options to purchase common stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period					4 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			150,000
Flex Pharma, Inc. 2014 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized								2,070,200	1,451,087	116,754
Shares remaining available for grant of stock awards					566,323		566,323