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		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Numerator for basic and diluted earnings per share:
Net income (loss)	$ 40,228	$ (93,337)	$ 43,534	$ (55,705)
Denominator:
Basic shares outstanding	58,161	60,369	58,799	60,585
Dilutive effect of equity-based compensation awards	107	0	99	0
Dilutive shares outstanding	58,268	60,369	58,898	60,585
Basic earnings per share (in USD per share)	$ 0.69	$ (1.55)	$ 0.74	$ (0.92)
Diluted earnings per share (in USD per share)	$ 0.69	$ (1.55)	$ 0.74	$ (0.92)