Warrants to Purchase Common Stock (Details)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010 Warrants Issued In 2003 [Member] October 24 2013 [Member]	Dec. 31, 2010 Warrants Issued In 2003 [Member] October 27 2013 [Member]	Dec. 31, 2010 Warrants Issued In 2004 [Member] October 27 2013 [Member]	Dec. 31, 2010 Warrants Issued In 2004 [Member] May 4 2014 [Member]	Dec. 31, 2010 Warrants Issued In 2004 [Member] October 27 2013 One [Member]	Dec. 31, 2010 Warrants Issued In 2005 [Member] Expired [Member]	Dec. 31, 2010 Warrants Issued In 2006 [Member] Expired [Member]	Dec. 31, 2010 Warrants Issued In 2006 [Member] Expired One [Member]	Dec. 31, 2010 Warrants Issued In 2007 [Member]	Dec. 31, 2010 Warrants Issued In 2008 [Member] May 23 2013 [Member]	Dec. 31, 2010 Warrants Issued In 2010 [Member]	Dec. 31, 2010 Warrants Issued In 2010 [Member] January 25 2015 [Member]
Class of Warrant or Right, Outstanding - Beginning balance	1,232,767	1,339,786
Class of Warrant or Right Issued			2,163	2,163	117,642	19,609	117,640	138,461	86,538	20,481		108,169		865,381
Class of Warrant or Right Exercised	(70,802)										(51,922)
Class of Warrant or Right Expired		(107,019)											(86,539)
Class of Warrant or Right, Outstanding - Ending balance	1,161,965	1,232,767
Class of Warrant or Right, Exercise Price of Warrants or Rights - Beginning balance	9.38	9.42
Warrants Issued Weighted Average Exercise Price			2.89	8.67	2.89	2.89	8.67	7.22	9.82	9.82		10.40		10.40
Warrants Exercised Weighted Average Exercise Price	8.59												7.22
Warrants Expired Weighted Average Exercise Price		9.82									7.22
Class of Warrant or Right, Exercise Price of Warrants or Rights - Ending balance	9.43	9.38