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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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 share-based awards, other than options, awarded to employees as compensation.

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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.

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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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Stock Based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2012
2017 Incentive Plan \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum shares available under equity incentive plan		800,000
Stock based compensation expense	$ 1,700	$ 2,400	$ 892
Unrecognized compensation expense	$ 1,500
Compensation cost not yet recognized, period for recognition	2 years 2 months 12 days
2017 Incentive Plan \| Time Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares awarded under equity incentive plan	25,729
2017 Incentive Plan \| Performance Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares awarded under equity incentive plan	62,919
2012 Incentive Plan \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum shares available under equity incentive plan				500,000
Shares awarded under equity incentive plan	0
Stock based compensation expense	$ 1,700	$ 2,400	$ 892
Unrecognized compensation expense	$ 1,500
Compensation cost not yet recognized, period for recognition	2 years 2 months 12 days
2017 Incentive Plan and 2012 Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares vested	324,978
Number of shares vested, weighted average fair value	$ 15.21
2017 Incentive Plan and 2012 Incentive Plan \| Time Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares awarded under equity incentive plan	25,729
Number of shares vested	261,105
Number of shares vested, weighted average fair value	$ 8.46
2017 Incentive Plan and 2012 Incentive Plan \| Performance Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares awarded under equity incentive plan	62,919
Number of shares vested	63,873
Number of shares vested, weighted average fair value	$ 7.76