Financing (Details 9) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Fair value adjustments:
Compound embedded derivatives	$ 17	$ (29)	$ 27	$ (273)
Warrant derivatives	(2)	(38)	(1)	(618)
Hybrid instruments	(154)	$ 1,369	3,077	$ 2,542
Fair Value, Inputs, Level 3 [Member]
Debt Conversion [Line Items]
Beginning balance, December 31, 2014:			37,393
Fair value adjustments:
Compound embedded derivatives			26
Warrant derivatives			0
Hybrid instruments			3,077
Conversions:
August 24, 2006 financing			(12)
August 14, 2009 financing			(16)
July 1, 2013 financing			(22)
September 15, 2014 financing			(20)
Ending balance, June 30, 2015	40,426		40,426
Fair Value, Inputs, Level 3 [Member] | Compound embedded derivatives [Member]
Debt Conversion [Line Items]
Beginning balance, December 31, 2014:			6
Fair value adjustments:
Compound embedded derivatives			27
Warrant derivatives			0
Hybrid instruments			0
Conversions:
August 24, 2006 financing			0
August 14, 2009 financing			0
July 1, 2013 financing			0
September 15, 2014 financing			0
Ending balance, June 30, 2015	33		33
Fair Value, Inputs, Level 3 [Member] | Warrant derivatives [Member]
Debt Conversion [Line Items]
Beginning balance, December 31, 2014:			2
Fair value adjustments:
Compound embedded derivatives			(1)
Warrant derivatives			0
Hybrid instruments			0
Conversions:
August 24, 2006 financing			0
August 14, 2009 financing			0
July 1, 2013 financing			0
September 15, 2014 financing			0
Ending balance, June 30, 2015	1		1
Fair Value, Inputs, Level 3 [Member] | Hybrid instruments [Member]
Debt Conversion [Line Items]
Beginning balance, December 31, 2014:			37,385
Fair value adjustments:
Compound embedded derivatives			0
Warrant derivatives			0
Hybrid instruments			3,077
Conversions:
August 24, 2006 financing			(12)
August 14, 2009 financing			(16)
July 1, 2013 financing			(22)
September 15, 2014 financing			(20)
Ending balance, June 30, 2015	$ 40,392		$ 40,392