Number of equity incentive plans.

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.

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- Definition

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

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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

+ Details

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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

Value, before forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

No definition available.

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- Definition

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

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Stock Options and Restricted Stock - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) Incentive_Plan shares	Sep. 30, 2017 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| Incentive_Plan			3
Market value of shares granted \| $			$ 500	$ 700
Stock options exercised, Shares \| shares			15,000	0
Proceeds from stock option exercises \| $			$ 67
Share-based compensation expense \| $	$ 300	$ 300	$ 1,100	$ 1,300
Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock granted, shares \| shares			3,304	7,434
Restricted Stock Units (RSUs) [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock granted, shares \| shares			5,761	6,454