Financing (Details 6) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Debt Conversion [Line Items]
Gain (loss) from changes in fair value of hybrid instruments	$ (628)	$ (433)	$ (1,173)	$ 24,054
Debentures 2006 Series [Member]
Debt Conversion [Line Items]
Gain (loss) from changes in fair value of hybrid instruments	(170)	(105)	(61)	5,609
Debentures 2007 Series [Member]
Debt Conversion [Line Items]
Gain (loss) from changes in fair value of hybrid instruments	(71)	(115)	(14)	5,795
Debentures 2008 Series [Member]
Debt Conversion [Line Items]
Gain (loss) from changes in fair value of hybrid instruments	(145)	(121)	(58)	7,006
Debentures 2009 Series [Member]
Debt Conversion [Line Items]
Gain (loss) from changes in fair value of hybrid instruments	(13)	(18)	(5)	1,352
Debentures 2010 Series [Member]
Debt Conversion [Line Items]
Gain (loss) from changes in fair value of hybrid instruments	0	(46)	0	2,654
Debentures 2011 Series [Member]
Debt Conversion [Line Items]
Gain (loss) from changes in fair value of hybrid instruments	(94)	(12)	(26)	625
Debentures 2012 Series [Member]
Debt Conversion [Line Items]
Gain (loss) from changes in fair value of hybrid instruments	(34)	(16)	(45)	1,013
Debentures 2013 Series [Member]
Debt Conversion [Line Items]
Gain (loss) from changes in fair value of hybrid instruments	$ (101)	$ 0	$ (964)	$ 0