Fair value of options non vested. Excludes equity instruments other than options.

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Stockholders Equity Note [Line Items]

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- Definition

Number of warrants or rights outstanding.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Section S99
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Aggregate number of common shares reserved for future issuance.

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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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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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.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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

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No definition available.

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

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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

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Stockholders' Equity - Additional Information (Details) - USD ($) $ in Millions		1 Months Ended		3 Months Ended
	Dec. 08, 2017	Mar. 29, 2018	May 19, 2011	Mar. 31, 2018	Dec. 31, 2017	Apr. 03, 2017	Jun. 02, 2016
Stockholders Equity Note [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance						800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term				6 years 8 months 12 days
Proceeds from Stock Options Exercised				$ 1.5
Share Based Compensation Arrangement By Share Based Payment Award Options Non Vested In Period Fair Value 1				$ 10.1
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term				9 years 10 months 24 days
Non-qualified Stock Option [Member]
Stockholders Equity Note [Line Items]
Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Grants In Period, Gross				220,000
Share-based Compensation Arrangement by Share-based Payment Award, Description				one-third will vest on the first anniversary of the date of grant, March 8, 2019; and the remaining two-thirds will vest in 24 equal monthly installments, with the option becoming fully vested on March 8, 2021
Warrant [Member]
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term				2 years 4 months 24 days
Class of Warrant or Right, Outstanding				15,296
Common Stock [Member]
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				248,762
Employees [Member]
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		131,559
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
Chief Financial Officer and Chief Operating Officer [Member] \| Non-qualified Stock Option [Member]
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				3 years
Restricted Stock Units (RSUs) [Member]
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	120,000
2010 Stock Incentive Plan [Member]
Stockholders Equity Note [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number				585,584
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized			793,440
2014 Stock Incentive Plan [Member]
Stockholders Equity Note [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number				3,336,988
Common Stock, Capital Shares Reserved for Future Issuance							4,160,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant				181,078
2017 Stock Incentive Plan [Member]
Stockholders Equity Note [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number				437,550
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant				362,450
Restricted Stock [Member]
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Beginning Balance				251,559	120,000