QUARTERLY INFORMATION (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
QUARTERLY INFORMATION (UNAUDITED)
Revenues	$ 15,574	$ 20,805	$ 26,217	$ 25,777	$ 41,014	$ 40,513	$ 34,994	$ 34,202	$ 88,373	$ 150,723
Gross profit	2,966	8,514	12,938	12,692	23,974	26,618	25,235	24,136	37,110	99,963
Net income	(246,354)	(186,061)	(85,276)	(102,272)	1,340	3,726	10,754	8,210	(619,963)	24,030
Net income applicable to common stockholders	$ (246,357)	$ (186,063)	$ (85,279)	$ (102,274)	$ 1,338	$ 3,723	$ 10,752	$ 8,207	$ (619,973)	$ 24,020
Earnings per share
Basic (in dollars per share)	$ (2.89)	$ (2.29)	$ (1.05)	$ (1.26)	$ 0.02	$ 0.05	$ 0.15	$ 0.11	$ (7.55)	$ 0.31
Diluted (in dollars per share)	$ (2.89)	$ (2.29)	$ (1.05)	$ (1.26)	$ 0.02	$ 0.05	$ 0.15	$ 0.11	$ (7.55)	$ 0.31