Condensed Consolidated Statement of Changes in Stockholders' Deficit - 6 months ended Jun. 30, 2017 - USD ($) $ in Thousands	Total	Preferred Shares	Common Shares	Treasury Stock	Additional Paid-in Capital	Accumulated Deficit
Balance at Dec. 31, 2016	$ (9,058)	$ 24,364	$ 207,166	$ (1,498)	$ 964,914	$ (1,204,004)
Balance (in shares) at Dec. 31, 2016		328,184,640	270,183,201	(819,505)
Exercise of stock options	$ 396		$ 139		257
Exercise of stock options (in shares)	221,345		221,345
Vesting of restricted stock units	$ (2,437)		$ 1,251	$ (2,404)	(1,284)
Vesting of restricted stock units (in shares)			1,997,311	(790,294)
Stock-based compensation	6,910				6,910
Loss for the period	(34,575)					(34,575)
Balance at Jun. 30, 2017	$ (38,764)	$ 24,364	$ 208,556	$ (3,902)	$ 970,797	$ (1,238,579)
Balance (in shares) at Jun. 30, 2017		328,184,640	272,401,857	(1,609,799)