Stock Options and Restricted Stock - Additional Information (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) Incentive_Plan shares	Mar. 31, 2015 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| Incentive_Plan	3
Stock options exercised, Shares \| shares	35,679	74,250
Proceeds from stock option exercises \| $	$ 454	$ 557
Share-based compensation expense \| $	$ 200	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 \| $		$ 300
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 \| $	$ 900
Restricted Stock Units (RSUs) [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common stock granted \| shares		6,757
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 \| shares	17,063
Restricted Stock Units (RSUs) [Member] \| Non-employee Director [Member] \| 2012 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common stock granted \| shares	17,063

Number of equity incentive plans.

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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
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-SubTopic 10
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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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- 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

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

+ References

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

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-Name Regulation S-X (SX)
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-Section 02
-Paragraph 29, 30
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