Percent of payout for performance based stock units

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- Definition

Remaining contract life of exercisable stock option.

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No definition available.

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Remaining contract life of outstanding stock options.

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- Definition

Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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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

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

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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).

+ References

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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

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

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

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- Definition

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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No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

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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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ References

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

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

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

+ References

No definition available.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

No definition available.

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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

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share options (or share units) exercised during the current period.

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Share-Based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	Mar. 31, 2019	Feb. 20, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Share-based Compensation (Details Textual)
Stock-based compensation expenses			$ 1,692	$ 1,359
Share-based compensation (capitalized)			200	100
Employee Stock Option [Member]
Share-based Compensation (Details Textual)
Stock option award unrecognized compensation	$ 5,600		5,600
Stock option award outstanding aggregate intrinsic value	$ 100		100
Remaining contract life of outstanding stock options.	6 years 11 months
Remaining contract life of exercisable stock option	3 years 6 months
Stock option award exercisable aggregate intrinsic value			$ 0
Stock Option Activity
Options outstanding, beginning of period, shares	640,378		640,378		644,575
Options outstanding, beginning of period, weighted average price	$ 28.29		$ 28.29		$ 28.28
Options granted, shares			0
Options granted, weighted average price			$ 0.00
Options forfeited, shares			(4,197)
Options forfeited, weighted average share price			$ 26.96
Options canceled, shares			0
Options canceled, weighted average price			$ 0.00
Options exercised, shares			0
Options exercised, weighted average price			$ 0.00
Options exercisable, end of period, shares	195,178		195,178
Options exercisable, end of period, weighted average price	$ 28.87		$ 28.87
Restricted Stock Units (RSUs) [Member]
Share-based Compensation (Details Textual)
Stock option award unrecognized compensation	$ 6,400		$ 6,400
Unrecognized compensation expense weighted-average period			2 years 5 months
Restricted stock activity
Restricted shares outstanding, beginning of period, shares			340,678
Restricted shares outstanding, beginning of period, weighted average price			$ 27.64
Restricted shares granted, shares			62,650
Restricted shares granted, weighted average price			$ 22.34
Restricted shares forfeited, shares			(8,044)
Restricted shares forfeited, weighted average price			$ 27.47
Restricted shares vested, shares			(61,263)
Restricted shares vested, weighted average price			$ 27.07
Restricted shares outstanding, end of period, shares	334,021		334,021
Restricted shares outstanding, end of period, weighted average price	$ 26.76		$ 26.76
Performance-based stock unit [Member]
Share-based Compensation (Details Textual)
Stock option award unrecognized compensation	$ 800		$ 800
Unrecognized compensation expense weighted-average period	1 year 11 months
Restricted stock activity
Restricted shares granted, shares		30,700
Restricted shares granted, weighted average price		$ 41.66
Restricted shares vested, shares			0
Percent of payout for performance based stock units	100.00%	150.61%	100.00%
Minimum [Member] \| Employee Stock Option [Member]
Share-based Compensation (Details Textual)
Stock option award vesting period			1 year
Minimum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation (Details Textual)
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			1 year
Minimum [Member] \| Performance-based stock unit [Member]
Restricted stock activity
Percent of payout for performance based stock units		0.00%
Maximum [Member] \| Employee Stock Option [Member]
Share-based Compensation (Details Textual)
Stock option award vesting period			5 years
Maximum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation (Details Textual)
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			5 years
Maximum [Member] \| Performance-based stock unit [Member]
Share-based Compensation (Details Textual)
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			3 years
Restricted stock activity
Percent of payout for performance based stock units		200.00%
General and Administrative Expense [Member]
Share-based Compensation (Details Textual)
Stock-based compensation expenses			$ 1,700	$ 1,400