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Stock Options and Restricted Stock - Additional Information (Detail) (USD $)	6 Months Ended
	Jun. 30, 2014 Incentive_Plan	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans	3
Market value of restricted shares granted	$ 200,000
Stock options exercised, Shares	123,167	125,000
Proceeds from stock option exercises	1,127,000	1,125,000
Share-based compensation expense	$ 400,000	$ 700,000
Restricted Stock Units (RSUs) [Member] | Non-Employee Directors [Member] | 2010 Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common stock granted	4,866

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Grant Date Fair Market Value of Option Grant

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Number Of Equity Incentive Plans

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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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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.

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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).

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

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