EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Numerator:
Net income	$ 14,896	$ 12,727
Denominator:
Denominator for basic earnings per share	26,236	26,359
Dilutive effect of unvested employee stock awards	185	166
Denominator for diluted earnings per share	26,421	26,525
Earnings per share:
Basic	$ 0.57	$ 0.48
Diluted	$ 0.56	$ 0.48
Additional Disclosure
Employee stock awards excluded from computation of diluted earnings per share	0	0

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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

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