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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

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-Glossary Financing Activities
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Period Type:	duration

- 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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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the equity-based award expires, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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.

+ Details

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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.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

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

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Stock Options and Restricted Stock - Additional Information (Detail) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2016 USD ($) Incentive_Plan shares	Jun. 30, 2015 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| Incentive_Plan		3
Stock options exercised, Shares		38,879	97,850
Proceeds from stock option exercises \| $		$ 501	$ 834
Share-based compensation expense \| $	$ 500	$ 700	400
2005 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan expiration date		Oct. 27, 2015
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market value of restricted shares granted \| $			$ 1,400
Restricted Stock Units (RSUs) [Member] \| 2012 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market value of restricted shares granted \| $		$ 1,900
Restricted Stock Units (RSUs) [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common stock granted			25,461
Restricted Stock Units (RSUs) [Member] \| Executive Officers [Member] \| 2012 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common stock granted		27,077
Restricted Stock Units (RSUs) [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common stock granted			7,112
Restricted Stock Units (RSUs) [Member] \| Non-employee Directors [Member] \| 2012 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common stock granted		5,952