Financing (Details 8) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Debt Conversion [Line Items]
Gain from change in fair value of derivative liability - warrants	$ 437	$ 3,122
Series D Convertible Preferred Stock [Member]
Debt Conversion [Line Items]
Gain from change in fair value of derivative liability - warrants	77	608
Warrants With Debenture Attached Series 2008 [Member]
Debt Conversion [Line Items]
Gain from change in fair value of derivative liability - warrants	207	1,424
Warrants With Debenture Attached Series 2010 [Member]
Debt Conversion [Line Items]
Gain from change in fair value of derivative liability - warrants	71	480
Warrants With Debenture Attached Series 2011 [Member]
Debt Conversion [Line Items]
Gain from change in fair value of derivative liability - warrants	51	387
Warrants With Debenture Attached Series 2012 [Member]
Debt Conversion [Line Items]
Gain from change in fair value of derivative liability - warrants	$ 31	$ 223