Warrants Issued (Narrative) (Details)				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 June 2012 Warrant Y	Dec. 31, 2012 May 2012 Warrant Y	Dec. 31, 2011 November 2011 Warrant Y
Number of shares of common stock available for purchase				2,100,000	3,300,000	1,300,000
Warrant exercise price, per share	7.28	22.08	25.84	2.65	2.125	6.24
Warrant term, in years				5	3	5
Class of Warrant or Right, Date from which Warrants or Rights Exercisable				Jun. 30, 2013	Jul. 31, 2012	Nov. 30, 2011