Number of active stock based compensation plans.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Number of Shares

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Offering Period

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- Definition

Stock plans.

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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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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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The total fair value of shares issued during the period under a deferred compensation arrangement.

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Number of shares issued pursuant to the terms of a deferred 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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- 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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- Definition

Percentage of vesting of share-based compensation awards.

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

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Stock Plans (Details Textual) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($) share_based_compensation_plan $ / shares shares	Jun. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2018 USD ($) share_based_compensation_plan shares $ / shares	Jun. 30, 2017 USD ($) $ / shares shares
Stock Plans (Textual) [Abstract]
Stock-based compensation plans (in shares) \| share_based_compensation_plan	2		2
Stock options granted during the period (in shares) \| shares	30,000	45,000	30,000	45,000
Weighted average grant date fair value (in dollars per share) \| $ / shares	$ 2.75	$ 2.95	$ 2.75	$ 2.95
Stock-based compensation expense	$ 2,747	$ 2,254	$ 5,371	$ 3,792
Bonuses settled in stock
Stock Plans (Textual) [Abstract]
Stock compensation expense	700	800	1,500	1,300
Bonuses settled in stock \| Director
Stock Plans (Textual) [Abstract]
Settled bonuses, previously earned under plan			$ 268
Number shares of fully vested common stock and restricted stock units \| shares			46,923
Stock compensation expense	65	72	$ 174	72
Bonuses settled in stock \| Annual Incentive Bonuses, 2017 Performance Period
Stock Plans (Textual) [Abstract]
Settled bonuses, previously earned under plan			3,000
Bonuses settled in stock \| Annual Incentive Bonuses, 2016 Performance Period
Stock Plans (Textual) [Abstract]
Settled bonuses, previously earned under plan	300	1,200
Stock options
Stock Plans (Textual) [Abstract]
Stock-based compensation expense	68	57	140	107
Restricted stock awards
Stock Plans (Textual) [Abstract]
Stock-based compensation expense	23	100	$ 83	200
Director restricted stock unit awards
Stock Plans (Textual) [Abstract]
Restricted stock unit vesting period (in years)			1 year
Restricted stock unit awards
Stock Plans (Textual) [Abstract]
Stock-based compensation expense	$ 1,859	$ 1,236	$ 3,361	2,102
Restricted stock unit vesting period (in years)			4 years
Number of unrestricted shares of common stock to be received upon vesting \| shares			1
Restricted stock unit awards \| Bonuses settled in stock \| Annual Incentive Bonuses, 2016 Performance Period
Stock Plans (Textual) [Abstract]
Number shares of fully vested common stock and restricted stock units \| shares	42,662	89,730
Restricted stock unit awards \| Service-based
Stock Plans (Textual) [Abstract]
Stock-based compensation expense	$ 1,102	$ 669	$ 2,186	1,337
Market condition restricted stock units \| Minimum
Stock Plans (Textual) [Abstract]
Potential vesting percentages			0.00%
Market condition restricted stock units \| Maximum
Stock Plans (Textual) [Abstract]
Potential vesting percentages			200.00%
Market condition restricted stock units \| Performance period one
Stock Plans (Textual) [Abstract]
Restricted stock unit vesting period (in years)			1 year
Market condition restricted stock units \| Performance period two
Stock Plans (Textual) [Abstract]
Restricted stock unit vesting period (in years)			2 years
Market condition restricted stock units \| Performance period three
Stock Plans (Textual) [Abstract]
Restricted stock unit vesting period (in years)			3 years
Employee stock purchase plan
Stock Plans (Textual) [Abstract]
Stock-based compensation expense	$ 50	$ 20	$ 79	$ 53
Discount rate from market value on offering date			85.00%
Offering period			6 months
Fully vested common stock \| Bonuses settled in stock \| Annual Incentive Bonuses, 2017 Performance Period
Stock Plans (Textual) [Abstract]
Number shares of fully vested common stock and restricted stock units \| shares			506,017
Fully vested common stock \| Bonuses settled in stock \| Annual Incentive Bonuses, 2016 Performance Period
Stock Plans (Textual) [Abstract]
Number shares of fully vested common stock and restricted stock units \| shares		142,582