NET INCOME (LOSS) PER SHARE (Basic and Diluted Net Income Per Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Basic net income per share:
Net income (loss)	$ 17,166	$ 9,807	$ 4,825	$ 2,206	$ 13,771	$ (30,330)	$ 1,520	$ (6,028)	$ 34,004	$ (21,067)	$ 41,204
Weighted average common shares outstanding (in shares)									32,432	28,416	28,232
Basic net income per common share (in dollars per share)									$ 1.05	$ (0.74)	$ 1.46
Diluted net income per share:
Net income (loss)	$ 17,166	$ 9,807	$ 4,825	$ 2,206	$ 13,771	$ (30,330)	$ 1,520	$ (6,028)	$ 34,004	$ (21,067)	$ 41,204
Weighted average common shares outstanding (in shares)									32,432	28,416	28,232
Effect of dilutive securities:
Stock options and restricted stock (in shares)									528	0	284
Weighted average common shares for diluted earnings per share (in shares)									32,960	28,416	28,516
Diluted net income per common share (in dollars per share)									$ 1.03	$ (0.74)	$ 1.44