CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock	Common stock warrants	Additional paid-in capital	Accumulated other comprehensive income	Accumulated deficit
Beginning balance at Dec. 31, 2011	$ 27,305	$ 6	$ 6,247	$ 132,312	$ 8,945	$ (120,205)
Beginning balance (in shares) at Dec. 31, 2011		6,358,253
Increase (Decrease) in Stockholders' Equity
Net loss	(20,286)					(20,286)
Stock-based compensation expense	2,009			2,009
Costs of reorganization	(15)			(15)
Issuance of common stock, net of costs	19,886	4		19,882
Issuance of common stock, net of costs (in shares)		3,593,819
Issuance of warrants, net of costs	4,942		4,942
Net exercise of warrants	0		(36)	36
Net exercise of warrants (in shares)		5,653
Foreign currency translation	575				575
Unrealized loss on investments	0
Ending balance at Dec. 31, 2012	34,416	10	11,153	154,224	9,520	(140,491)
Ending balance (in shares) at Dec. 31, 2012		9,957,725
Increase (Decrease) in Stockholders' Equity
Net loss	(52,859)					(52,859)
Reclassification of warrants	(16,194)		(11,153)			(5,041)
Reclassification of stock option liability	1,369			1,369
Stock-based compensation expense	1,823			1,823
Issuance of common stock, net of costs	54,196	3		54,193
Issuance of common stock, net of costs (in shares)		3,337,500
Exercise of options for cash	540			540
Exercise of options for cash (in shares)		40,534
Exercise of warrants for cash	21			21
Exercise of warrants for cash (in shares)		2,896
Net exercise of warrants	2,586			2,586
Net exercise of warrants (in shares)		108,321
Unrealized loss on investments	(13)				(13)
Ending balance at Dec. 31, 2013	25,885	13	0	214,756	9,507	(198,391)
Ending balance (in shares) at Dec. 31, 2013	13,446,976	13,446,976
Increase (Decrease) in Stockholders' Equity
Net loss	(43,698)					(43,698)
Reclassification of warrants	36,931			36,931
Stock-based compensation expense	7,050			7,050
Exercise of options for cash	887	1		886
Exercise of options for cash (in shares)	76,224	76,224
Net exercise of warrants	993			993
Net exercise of warrants (in shares)	43,526	43,526
Unrealized loss on investments	14				14
Ending balance at Dec. 31, 2014	$ 28,062	$ 14	$ 0	$ 260,616	$ 9,521	$ (242,089)
Ending balance (in shares) at Dec. 31, 2014	13,566,726	13,566,726