CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Common Stock	Treasury	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance, shares (in shares) at Dec. 31, 2018		586,881,720	549,907
Beginning balance at Dec. 31, 2018	$ 1,791,291	$ 5,869	$ (1,791)	$ 3,004,422	$ (20,131)	$ (1,197,078)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation expense	4,457			4,457
Exercise of Common Stock options and warrants, shares (in shares)		19,232
Exercise of Common Stock options and warrants	(3)			(3)
2025 convertible notes including share lending arrangement (in shares)		29,250,000
2025 convertible notes including share lending arrangement	50,852	$ 293		50,559
Net loss	(80,762)					(80,762)
Other comprehensive loss	(3,098)				(3,098)
Ending balance, shares (in shares) at Mar. 31, 2019		616,150,952	549,907
Ending balance at Mar. 31, 2019	1,762,737	$ 6,162	$ (1,791)	3,058,509	(23,229)	(1,276,914)
Beginning balance, shares (in shares) at Dec. 31, 2019		670,378,701	549,907
Beginning balance at Dec. 31, 2019	1,614,759	$ 6,704	$ (1,791)	3,142,993	(22,070)	(1,511,077)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation expense	2,451			2,451
Exercise of Common Stock options and warrants	0
2025 convertible notes including share lending arrangement	0
Net loss	(59,132)					(59,132)
Other comprehensive loss	(8,117)				(8,117)
Ending balance, shares (in shares) at Mar. 31, 2020		670,378,701	549,907
Ending balance at Mar. 31, 2020	$ 1,548,619	$ 6,704	$ (1,791)	$ 3,145,444	$ (30,187)	$ (1,571,551)