EARNINGS 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, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Numerator for basic and diluted earnings per share:
Net income	$ 10,395	$ 28,672	$ 3,306	$ 37,632
Denominator:
Basic shares outstanding	58,590	60,665	58,732	60,695
Dilutive effect of equity-based compensation awards	120	113	100	127
Dilutive shares outstanding	58,710	60,778	58,832	60,822
Basic earnings per share (in USD per share)	$ 0.18	$ 0.47	$ 0.06	$ 0.62
Diluted earnings per share (in USD per share)	$ 0.18	$ 0.47	$ 0.06	$ 0.62