Licensing Agreements (Details)	12 Months Ended				163 Months Ended	12 Months Ended
	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2008 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2012 Drexel University USD ($)	Dec. 31, 2012 Lankenau Institute for Medical Research IDO-1 USD ($)	Dec. 31, 2012 Lankenau Institute for Medical Research IDO-2 USD ($)	Dec. 31, 2012 Lankenau Institute for Medical Research 2009 Agreement USD ($)	Dec. 31, 2012 Georgia Health Sciences University USD ($)	Dec. 31, 2012 Regents of the University of California USD ($)	Dec. 31, 2012 Her Majesty the Queen in Right of Canada CAD
Licensing Agreements
Potential Milestone Payment per Licensed Product						$ 1,000,000	$ 1,360,000	$ 1,520,000	$ 610,000	$ 2,800,000	$ 285,000	205,000
Licensing Payments Under All In-Licensing Agreements	255,000	89,000	391,000		2,800,000
Licensing Payments [Abstract]
Stock issued for licensing			$ 201,000	$ 5,000
Stock issued for licensing (shares)			23,810