The aggregate unrecognized cost of equity-based awards expected to be recognized in the future.

No definition available.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards (which are expected to recognize) made to employees under equity-based compensation awards that have yet to vest during remainder of year.

+ References

No definition available.

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Percentage of restricted stock units granted as result of meeting growth rates

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award incentive stock options outstanding number.

+ References

No definition available.

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- Definition

The number of shares (or other type of equity) which are non-qualified options to purchase under the plan.

+ References

No definition available.

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- Definition

The percentage of number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award restricted stock options to purchase number of shares.

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No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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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

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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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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- Definition

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

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
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- Definition

Percentage of vesting of share-based compensation awards.

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

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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Share-Based Payment Arrangements (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, Granted	0	0
Other than options, forfeited	83,210	161,288
Vested		8,198
Long Term Incentive Plan 2005 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of incentive stock options outstanding	0
Share-based compensation arrangement by share-based payment award, non-qualified stock options to purchase number of shares	14,157
Long Term Incentive Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized	2,000,000
Share-based compensation arrangement by share-based payment award, restricted stock options to purchase number of shares	383,530
Stock options, Granted	0
Long Term Incentive Plan 2005 and 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested share-based compensation arrangements	$ 0
Prior To 2009 Incentive Stock Options [Member] \| Long Term Incentive Plan 2005 [Member] \| First Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Percentage	10.00%
Prior To 2009 Incentive Stock Options [Member] \| Long Term Incentive Plan 2005 [Member] \| Second Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Percentage	20.00%
Prior To 2009 Incentive Stock Options [Member] \| Long Term Incentive Plan 2005 [Member] \| Third Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Percentage	30.00%
Prior To 2009 Incentive Stock Options [Member] \| Long Term Incentive Plan 2005 [Member] \| Fourth Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Percentage	40.00%
Prior To 2009 Incentive Stock Options [Member] \| Long Term Incentive Plan 2005 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation incentive stock options grant under incentive plan termination period	5 years
Prior To 2009 Incentive Stock Options [Member] \| Long Term Incentive Plan 2005 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation incentive stock options grant under incentive plan termination period	10 years
Incentive Stock Options 2010 [Member] \| Long Term Incentive Plan 2005 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation incentive stock options grant under incentive plan termination period	10 years
Non Qualified Stock Options [Member] \| Long Term Incentive Plan 2005 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	100.00%
Stock-based compensation incentive stock options grant under incentive plan termination period	10 years
Share-based payment, award vesting period	6 months
Non Qualified Stock Options [Member] \| Long Term Incentive Plan 2005 [Member] \| 200,000 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation incentive stock options grant under incentive plan termination period	10 years
Number of options vested or expected to vest	200,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested share-based compensation arrangements	$ 1,700
Employee Service Share-based Compensation Nonvested Awards, Total Compensation Cost Expected to Recognize During Remainder of Year	400
Employee Service Share-based Compensation Nonvested Awards, Total Compensation Cost Expected to Recognize During Remainder of Year Two	600
Employee Service Share-based Compensation Nonvested Awards, Total Compensation Cost Expected to Recognize During Year Three	100
Employee Service Share-based Compensation Nonvested Awards, Total Compensation Cost Expected to Recognized	1,100
Allocated share-based compensation expense	57	$ 44
Income tax benefit of share-based payments recognized in income	$ 12	$ 9
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of restricted stock units granted as result of meeting growth rates	50.00%
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of restricted stock units granted as result of meeting growth rates	150.00%
Restricted Stock Units (RSUs) [Member] \| Long Term Incentive Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options, grant date fair value			$ 10.87	$ 10.20	$ 11.41	$ 11.10