NET INCOME PER COMMON SHARE - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Numerator:
Net income	$ 5,959	$ 10,365
Adjustment for Basic EPS:
Earning allocated to unvested shareholders	(87)	(191)
Adjusted net income	$ 5,872	$ 10,174
Denominator:
Weighted average common shares outstanding – Basic	46,783,158	46,661,559
Effect of dilutive shares:
Common stock equivalents arising from stock options and ESPP	837	2,151
Restricted stock awards and units and performance units	64,803	79,184
Weighted average common shares outstanding – Diluted	46,848,798	46,742,894
Basic	$ 0.13	$ 0.22
Diluted	$ 0.13	$ 0.22

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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 call options and warrants using the treasury stock method.

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Number of additional shares included in diluted EPS for potentially dilutive effect of nonvested equity-based payment award containing forfeitable rights to dividends or dividend equivalents, whether paid or unpaid.

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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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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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Amount of earnings (loss) distributed and earnings (loss) allocated to participating securities for the basic earnings (loss) per share or per unit calculation under the two-class method.

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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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