Potential Antidilutive Securities Excluded from Future Computations of Earnings, Amount

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Forfeiture Rate

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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.

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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

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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-Topic 230
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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

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.

+ References

No definition available.

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- Definition

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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- 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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- Definition

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

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Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended
Stock-Based Compensation (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	May 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Approved and authorized maximum number of shares to be issued (in shares)			2,400,000
Compensation expense related to stock based awards outstanding	$ 300	$ 400
Exercise of stock options (in shares)	146,765	103,855
Proceeds received upon exercise of stock options	$ 816	$ 623
Potential antidilutive securities excluded from future computations of earnings, amount	1,926,288	2,236,197
Total unrecognized compensation expense	$ 2,500
Share-based compensation cost not yet recognized, period for recognition		2 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, expiration period	10 years
Forfeiture rate	5.50%
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, vesting period	3 years
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, vesting period	5 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeiture rate	5.50%
2017 LTIP \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeiture rate	3.20%