Organization and Basis of Presentation (Details) (USD $)	1 Months Ended	6 Months Ended	12 Months Ended
	Jul. 31, 2012	Jun. 30, 2012 Segment	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2010
Organization and Basis of Presentation (Textual) [Abstract]
Number of operating segments		1
Losses incurred during the period		$ 319,630,000			$ 309,964,000
Cash and cash equivalents		24,491,000			39,904,000	54,188,000	33,589,000
Date of Incorporation		Jul. 22, 1980
Common stock outstanding, reverse stock split	0.167
Company name change effective from		Jul. 11, 2012
Decrease in future commitment			$ 629,000	$ 400,000