The number of purchase periods within an offering period.

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Length of time of a purchase period related to the employee stock purchase plan.

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The number of vested and unvested awards modified under an equity-based compensation plan.

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No definition available.

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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.

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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.

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Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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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.

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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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No definition available.

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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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- Definition

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

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No definition available.

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

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

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

+ References

No definition available.

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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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The number of employees affected by the modification of an equity-based compensation plan.

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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.

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

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Stock-Based Compensation - Additional Information (Details)			1 Months Ended		12 Months Ended
	Oct. 07, 2016 shares	Sep. 20, 2016 item shares	Dec. 31, 2016 USD ($) employee $ / shares shares	May 31, 2014 USD ($) employee $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Nov. 30, 2016 $ / shares	Apr. 30, 2014 $ / shares
Share-based Compensation
Total grant date fair value of options vested \| $					$ 622,000	$ 353,000	$ 332,000
Weighted-average grant date fair value of options granted					$ 4.52	$ 4.42	$ 1.82
Number of stock options granted \| shares					563,523	123,830
Total unrecognized compensation expense related to unvested options \| $			$ 3,400,000		$ 3,400,000
Unrecognized compensation expense, weighted-average period expected to be recognized					3 years 1 month 6 days
Stock-based compensation expense \| $					$ 1,141,000	$ 416,000	$ 799,000
Options remained outstanding \| shares			1,414,730		1,414,730	927,175	852,639
Weighted-average exercise price (per share)			$ 5.28		$ 5.28	$ 4.43	$ 4.42
Exercise price (in dollars per share)			5.28		$ 5.28	$ 4.43	$ 4.42
Employees
Share-based Compensation
Stock-based compensation expense \| $					$ 1,100,000	$ 407,000	$ 776,000
Weighted-average exercise price (per share)			$ 6.63	$ 4.42	$ 6.63			$ 15.86
Number of vested and unvested stock option award modified \| shares			396,028	333,774
Exercise price (in dollars per share)			$ 6.63	$ 4.42	6.63			$ 15.86
Number of employees affected \| employee			77	75
Incremental modification value \| $			$ 629,000	$ 939,000
Employees \| Immediate vesting
Share-based Compensation
Stock-based compensation expense \| $				207,000
Incremental modification value \| $			140,000
Employees \| Remaining vesting
Share-based Compensation
Incremental modification value \| $			$ 489,000	$ 732,000
Non-Employee
Share-based Compensation
Weighted-average grant date fair value of options granted					$ 7.51
Number of stock options granted \| shares					8,073		23,606
Stock-based compensation expense \| $					$ 23,000	$ 9,000	$ 23,000
Options remained outstanding \| shares			31,990		31,990	15,498	15,498
Weighted-average exercise price (per share)			$ 5.26		$ 5.26	$ 4.42	$ 4.42
Exercise price (in dollars per share)			$ 5.26		$ 5.26	$ 4.42	$ 4.42
Minimum \| Employees
Share-based Compensation
Weighted-average exercise price (per share)									$ 7.54
Exercise price (in dollars per share)									7.54
Maximum \| Employees
Share-based Compensation
Weighted-average exercise price (per share)									13.52
Exercise price (in dollars per share)									$ 13.52
2016 Employee Incentive Plan
Share-based Compensation
Maximum number of common stock shares may be issued under the plan \| shares	500,000
Annual increases in the number of shares available for issuance, percentage of outstanding capital stock	3.00%
2016 Employee Incentive Plan \| Incentive Stock Options \| Maximum
Share-based Compensation
Number of shares issued (in shares) \| shares	500,000
2016 Employee Stock Purchase Plan
Share-based Compensation
Maximum number of common stock shares may be issued under the plan \| shares		96,153
Annual increases in the number of shares available for issuance, percentage of outstanding capital stock		1.00%
Number of purchase periods \| item		2
Length of time of purchase period (in months)		6 months
2008 Equity Incentive Plan
Share-based Compensation
Options remained outstanding \| shares			1,257,230		1,257,230
Vesting period					4 years
Exercise period					10 years
2008 Equity Incentive Plan \| Incentive Stock Options \| Minimum
Share-based Compensation
Percentage of exercise price of fair market value of stock at the date of grant					100.00%
2008 Equity Incentive Plan \| Incentive Stock Options \| Maximum
Share-based Compensation
Percentage of exercise price of fair market value of stock at the date of grant					110.00%