EARNINGS (LOSS) PER SHARE (Computation of Basic and Diluted Earnings Per Share)(Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Numerator for basic and diluted earnings per share:
Net income (loss)	$ 3,966	$ 10,395	$ (16,905)	$ 3,306
Denominator:
Basic shares outstanding (in shares)	57,549	58,590	57,599	58,732
Dilutive effect of equity-based compensation awards (in shares)	129	120	0	100
Dilutive shares outstanding (in shares)	57,678	58,710	57,599	58,832
Basic earnings (loss) per share (in USD per share)	$ 0.07	$ 0.18	$ (0.29)	$ 0.06
Diluted earnings (loss) per share (in USD per share)	$ 0.07	$ 0.18	$ (0.29)	$ 0.06

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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 consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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