Increase percentage of common stock outstanding.

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- Definition

Number of incentive plans.

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- Definition

Plan termination date.

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Outstanding Intrinsic Value

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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.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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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.

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Discount rate from fair value on offering date that participants pay for shares.

+ References

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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-Publisher FASB
-Name Accounting Standards Codification
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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).

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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.

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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.

+ References

No definition available.

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- Definition

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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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.

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- Definition

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

+ References

No definition available.

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Stock Incentive Plan - Additional Information (Detail)		1 Months Ended	6 Months Ended
Stock Incentive Plan - Additional Information (Detail)	Jan. 01, 2016	Mar. 31, 2016 shares	Jun. 30, 2018 USD ($) Incentive_Plan $ / shares shares	Dec. 31, 2017 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of incentive plans \| Incentive_Plan			3
Options to purchase of shares of common stock			3,402,163	2,246,857
Exercise price per share of common stock \| $ / shares			$ 6.07	$ 4.87
Fair value of a common stock percentage			100.00%
Awards granted, vesting period			4 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted in term years			10 years
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation \| $			$ 8,780,414
Weighted average recognition period			2 years 11 months 23 days
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted, vesting period			4 years
Unamortized stock-based compensation \| $			$ 1,300,573
Weighted average grant date fair value of shares \| $ / shares			$ 8.60
Weighted average remaining recognition period			3 years 2 months 16 days
Aggregate intrinsic value of options outstanding \| $			$ 1,700,000
2004 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plans, contractual term			Seven years
Stock incentive plan, termination date			2010-08
Options to purchase of shares of common stock			23,954
Exercise price per share of common stock \| $ / shares			$ 3.24
2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase of shares of common stock			413,130
Exercise price per share of common stock \| $ / shares			$ 1.58
2013 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase of shares of common stock			2,965,079
Exercise price per share of common stock \| $ / shares			$ 6.72
Percentage of increase in common shares outstanding	6.00%
Shares of common stock underlying restricted stock units outstanding			212,297
Common stock available for issuance			528,406
2016 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance			191,778
Issuance of common stock authorized		223,263
Percentage increase in number of shares of common stock reserved for issuance		1.00%
Share-based compensation arrangement by share-based payment award, closing price on the applicable offering commencement			85.00%
Share-based compensation arrangement by share-based payment award, closing price on the applicable offering termination date			85.00%
Share-based compensation arrangement by share-based payment award, description			In March 2016, the Company’s board of directors approved the 2016 Employee Stock Purchase Plan (2016 ESPP), which became effective in June 2016 following the approval of the Company’s stockholders. The 2016 ESPP authorizes the initial issuance of up to a total of 223,263 shares of the Company’s common stock to participating employees. The number of shares reserved for issuance under the 2016 ESPP automatically increases on the first business day of each fiscal year, commencing in 2017, by a number equal to the lesser of (i) 1% of the shares of common stock outstanding on the last business day of the prior fiscal year; or (ii) the number of shares determined by the Company’s Board of Directors. Unless otherwise determined by the administrator of the 2016 ESPP, two offering periods of six months’ duration will begin each year on January 1 and July 1. Participating employees purchase stock under the 2016 ESPP at a price equal to the lower of 85% of the closing price on the applicable offering commencement date or 85% of the closing price on the applicable offering termination date.