Financing (Details 7) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Face Value	$ 28,887
Fair Value	64,292	16,458
Stock Shares	22,696,138
Debentures 2006 Series [Member]
Face Value	6,180
Fair Value	14,758
Stock Shares	5,196,283
Debentures 2007 Series [Member]
Face Value	6,856
Fair Value	17,172
Stock Shares	6,098,480
Debentures 2008 Series [Member]
Face Value	6,468
Fair Value	15,492
Stock Shares	5,487,497
Debentures 2009 Series [Member]
Face Value	1,644
Fair Value	3,565
Stock Shares	1,243,390
Debentures 2010 Series [Member]
Face Value	3,806
Fair Value	7,178
Stock Shares	2,512,724
Debentures 2011 Series [Member]
Face Value	1,954
Fair Value	3,080
Stock Shares	1,084,237
Debentures 2012 Series [Member]
Face Value	1,979
Fair Value	3,047
Stock Shares	$ 1,073,527