Reconciliation of Shares Used to Determine Net Income per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share Disclosure [Line Items]
Net income	$ 1,893us-gaap_NetIncomeLoss	$ 160us-gaap_NetIncomeLoss
Weighted average number of shares - basic	32,333,443	25,090,386
Weighted average number of shares outstanding - diluted	34,280,385	26,851,678
Warrants
Earnings Per Share Disclosure [Line Items]
Shares underlying	378,780	293,234
Options
Earnings Per Share Disclosure [Line Items]
Shares underlying	1,568,162	1,468,058

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

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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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