Number of stock appreciation rights granted during the period.

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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.

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- Definition

Amount of expense for employee benefit and equity-based compensation.

+ References

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.

+ References

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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

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

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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 highest quantity of shares an employee can purchase under the plan per period.

+ References

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- Definition

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

+ 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).

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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.

+ References

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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.

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-Publisher FASB
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- Definition

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

+ References

No definition available.

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- Definition

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

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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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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Share-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended	3 Months Ended	12 Months Ended
	Aug. 16, 2018	Jun. 05, 2017	Sep. 20, 2016	May 31, 2018	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Aug. 08, 2018	Dec. 31, 2016	Dec. 31, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional awards to be granted under the plan (in shares)							1,200,000
Shares available for future issuance (in shares)						699,376	1,023,378		615,207
Number of options granted to employees (in shares)						727,257	926,195
Stock options, exercise price at grant date (in USD per share)						$ 2.97	$ 5.15
Options outstanding (in shares)						1,671,666	1,399,484		825,130
Share-based compensation expense						$ 2,204	$ 3,758
Total intrinsic value of options exercised						95	901
Total unrecognized compensation expense related to non-vested share based compensation						$ 1,036	$ 2,343
Weighted average period for nonvested share recognition						1 year 9 months 15 days	1 year 5 months 4 days
CEO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employment agreement, number of SARs granted on a contingent basis (in shares)					1,000,000
SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SAR exercise price (in USD per share)						$ 3.8		$ 3.8
Employee share-based compensation expense						$ 8
2008 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares reserved for future issuance (in shares)										1,416,666
Additional awards to be granted under the plan (in shares)			0
Stock options expiration period						10 years
2016 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares reserved for future issuance (in shares)			833,333
Additional awards to be granted under the plan (in shares)	1,000,000	1,200,000
Maximum aggregate shares to be awarded to one person (in shares)	1,000,000		250,000
Shares available for future issuance (in shares)						699,376
Stock options expiration period						10 years
Employment agreement, number of SARs granted on a contingent basis (in shares)					1,000,000
Inducement Grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options granted to employees (in shares)				100,500
Stock options, exercise price at grant date (in USD per share)				$ 3.15
Stock options vesting period				3 years
Options outstanding (in shares)						100,500
Inducement Grants \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage						33.33%
Inducement Grants \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage						33.33%
Inducement Grants \| Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage						33.33%