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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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
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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

The number of grants made 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).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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).

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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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-Name Accounting Standards Codification
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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			9 Months Ended
	Sep. 30, 2017 USD ($) share_based_compensation_plan $ / shares shares	Mar. 31, 2017 USD ($) shares	Sep. 30, 2016 USD ($) $ / shares shares	Sep. 30, 2017 USD ($) share_based_compensation_plan shares $ / shares	Sep. 30, 2016 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	5,000		0	50,000	0
Average grant date fair value (in dollars per share) \| $ / shares	$ 3.12			$ 2.97
Stock-based compensation expense	$ 2,755		$ 1,097	$ 6,547	$ 3,759
Bonuses settled in stock
Stock Plans (Textual) [Abstract]
Stock compensation expense	700		0	1,900	900
Bonuses settled in stock \| Director
Stock Plans (Textual) [Abstract]
Settled bonuses, previously earned under plan	$ 71
Number shares of fully vested common stock and restricted stock units \| shares	12,904
Stock compensation expense	$ 92			164
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	62		49	169	134
Restricted stock awards
Stock Plans (Textual) [Abstract]
Stock-based compensation expense	100		200	$ 300	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	$ 1,775		$ 824	$ 3,876	$ 2,305
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 units, granted (in shares) \| shares	355,075		49,116	1,768,492	1,236,747
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	$ 1,124		$ 544	$ 2,460	$ 1,613
Restricted stock units, granted (in shares) \| shares	320,963			1,242,618	904,028
Weighted average grant date fair value (in dollars per share) \| $ / shares	$ 5.58		$ 5.09	$ 5.54	$ 5.56
Performance restricted stock unit awards
Stock Plans (Textual) [Abstract]
Restricted stock units, granted (in shares) \| shares	34,112			525,874	332,719
Weighted average grant date fair value (in dollars per share) \| $ / shares	$ 6.79			$ 6.77	$ 7.50
Market condition restricted stock units
Stock Plans (Textual) [Abstract]
Restricted stock units, granted (in shares) \| shares	34,112			367,874	286,495
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	$ 28		$ 53	$ 81	$ 189
Weighted average grant date fair value (in dollars per share) \| $ / shares	$ 1.45		$ 1.59	$ 1.28	$ 2.04
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, 2016 Performance Period
Stock Plans (Textual) [Abstract]
Number shares of fully vested common stock and restricted stock units \| shares		142,582