Minimum ownership percentage for 110% fair market value on the grant date.

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Aggregate number of common shares reserved for future issuance.

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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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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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 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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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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Number of share instruments newly issued under a share-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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Purchase price of common stock expressed as a percentage of its fair value.

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Share-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding under Equity plan		604,003	611,975	629,629
Stock options award, expiration		10 years
Weighted Average exercise Price of Options Outstanding		$ 5.37	$ 6.00	$ 6.30
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense related to unvested options		$ 186
Maturity period of weighted average period of compensation expenses		1 year 1 month 6 days
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options award, vesting period		3 years
Percentage holding for stock options exercise price		10.00%
Minimum \| Incentive Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price of stock option		100.00%
Minimum \| Incentive Stock Option \| Stockholders
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price of stock option		110.00%
Minimum \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Units award, requisite service period		3 years
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options award, vesting period		4 years
Maximum \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Units award, requisite service period		4 years
2013 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in number of shares reserve for issuance under amended Equity Plan	1,000,000
Number of shares issuable under Equity plan	1,321,428
Number of shares outstanding under Equity plan		597,342
Shares reserved for future		615,976
Options granted		40,000	469,600
Two Thousand And Four Stock Option Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding under Equity plan		5,383
Weighted Average exercise Price of Options Outstanding		$ 102.16
Other Stock Option Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding under Equity plan		1,278
Weighted Average exercise Price of Options Outstanding		$ 233.94