Earnings and Dividends per Share - Number of Shares Outstanding for Calculation of Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Abstract]
Basic net income and earnings per share, Numerator (Income)	$ 38	$ 3,100
Diluted earnings and earnings per share, Numerator (Income)	$ 38	$ 3,100
Basic net income and earnings per share, Denominator (Shares)	34,215,519	33,928,052
Common stock equivalents arising from stock options, restricted stock awards, and employee stock purchase plan, Denominator (Shares)	347,000	189,000
Diluted earnings and earnings per share, Denominator (Shares)	34,563,139	34,116,534
Basic net income and earning per share, Per Share Amount	$ 0.00	$ 0.09
Diluted earning and earning per share, Per Share Amount	$ 0.00	$ 0.09

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Net Income or Loss Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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