Earnings (Loss) Per Share - Computation of Earnings (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Numerator
Net income (loss) attributable to common shareholders, basic	$ 15,533	$ (42,766)	$ 3,554	$ (159,878)
Change in FV of embedded derivative income	(4,872)	0	(4,734)	0
Net income (loss) attributable to common shareholders, diluted	$ 11,265	$ (42,766)	$ 16	$ (159,878)
Denominator
Weighted average common shares outstanding, basic (in shares)	547,558,800	462,253,161	546,691,117	454,361,137
Effect of dilutive securities:
Stock options (in shares)	4,264,000	0	4,222,000	0
Warrants (in shares)	661,000	0	1,267,000	0
2033 Senior Notes (in shares)	4,556,000	0	4,556,000	0
Dilutive potential shares (in shares)	9,481,000	0	10,045,000	0
Weighted average common shares outstanding, diluted (in shares)	557,040,435	462,253,161	556,735,862	454,361,137
Earnings (loss) per share, basic (in dollars per share)	$ 0.03	$ (0.09)	$ 0.01	$ (0.35)
Earnings (loss) per share, diluted (in dollars per share)	$ 0.02	$ (0.09)	$ 0.00	$ (0.35)
Notes Due February 1, 2033 | Convertible Notes
Numerator
Add: Interest on 2033 Senior Notes	$ 604	$ 0	$ 1,196	$ 0