CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance beginning at Dec. 31, 2013	$ 203,234	$ 2,091	$ 612,900	$ (410,146)	$ (2,450)	$ 839
Balance (in shares) at Dec. 31, 2013		209,110,744
Non-cash compensation cost for stock options, ESPP and restricted stock	6,090	$ 0	6,090	0	0	0
Exercise of stock options/Purchase under ESPP	2,790	$ 14	2,776	0	0	0
Exercise of stock options/Purchase under ESPP, shares		1,411,550
Restricted stock issued as compensation	0	$ 0	0	0	0	0
Restricted stock issued as compensation, shares		15,000
Issuance of common stock	107,895	$ 288	107,607	0	0	0
Issuance of common stock,shares		28,750,000
Unrealized loss on marketable securities	(680)	$ 0	0	0	0	(680)
Foreign currency translation adjustment	(6,764)	0	0	0	0	(6,764)
Net loss	(82,947)	0	0	(82,947)	0	0
Balance ending at Dec. 31, 2014	229,618	$ 2,393	729,373	(493,093)	(2,450)	(6,605)
Balance ending (in shares) at Dec. 31, 2014		239,287,294
Non-cash compensation cost for stock options, ESPP and restricted stock	13,431	$ 0	13,431	0	0	0
Exercise of stock options/Purchase under ESPP	4,801	$ 19	4,782	0	0	0
Exercise of stock options/Purchase under ESPP, shares		1,950,748
Restricted stock issued as compensation	0	$ 0	0	0	0	0
Restricted stock issued as compensation, shares		25,000
Issuance of common stock	204,275	$ 292	203,983	0	0	0
Issuance of common stock,shares		29,163,620
Unrealized loss on marketable securities	42	$ 0	0	0	0	42
Foreign currency translation adjustment	(2,561)	0	0	0	0	(2,561)
Net loss	(156,937)	0	0	(156,937)	0	0
Balance ending at Dec. 31, 2015	292,669	$ 2,704	951,569	(650,030)	(2,450)	(9,124)
Balance ending (in shares) at Dec. 31, 2015		270,426,662
Non-cash compensation cost for stock options, ESPP and restricted stock	19,160	$ 0	19,160	0	0	0
Exercise of stock options/Purchase under ESPP	3,802	$ 13	3,789	0	0	0
Exercise of stock options/Purchase under ESPP, shares		1,254,735
Restricted stock issued as compensation	0	$ 0	0	0	0	0
Restricted stock issued as compensation, shares		20,000
Payment of capped call transactions and costs	(38,521)		(38,521)	0	0	0
Unrealized loss on marketable securities	54	$ 0	0	0	0	54
Foreign currency translation adjustment	(2,744)	0	0	0	0	(2,744)
Net loss	(279,966)	0	0	(279,966)	0	0
Balance ending at Dec. 31, 2016	$ (5,546)	$ 2,717	$ 935,997	$ (929,996)	$ (2,450)	$ (11,814)
Balance ending (in shares) at Dec. 31, 2016		271,701,397