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
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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 options awarded to employees as compensation.

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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.

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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).

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

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

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Share-based Compensation
Total grant date fair value of options vested	$ 107,000	$ 103,000
Number of stock options granted	74,000
Total unrecognized compensation expense related to unvested options	$ 3,200,000
Unrecognized compensation expense, weighted-average period expected to be recognized	2 years 9 months 18 days
Options remained outstanding	1,481,632		1,414,730
Weighted-average exercise price (per share)	$ 5.41		$ 5.28
Stock-based compensation expense	$ 431,000	111,000
Employees
Share-based Compensation
Weighted-average grant date fair value of options granted	$ 3.69
Stock-based compensation expense	$ 384,000	$ 105,000
Non-Employee
Share-based Compensation
Number of stock options granted	0	0
Options remained outstanding	31,990
Weighted-average exercise price (per share)	$ 5.26
Stock-based compensation expense	$ 11,000	$ 6,000
2016 Employee Incentive Plan
Share-based Compensation
Maximum number of common stock shares may be issued under the plan	500,000
Annual increases in the number of shares available for issuance, percentage of outstanding capital stock	3.00%
2016 Employee Stock Purchase Plan
Share-based Compensation
Maximum number of common stock shares may be issued under the plan	96,153
Annual increases in the number of shares available for issuance, percentage of outstanding capital stock	1.00%