Quarterly report pursuant to Section 13 or 15(d)

Warrant Liability (Details Textual)

Warrant Liability (Details Textual) (USD $)	9 Months Ended			1 Months Ended	3 Months Ended	1 Months Ended		1 Months Ended		2 Months Ended	1 Months Ended		1 Months Ended	2 Months Ended	9 Months Ended
Warrant Liability (Details Textual) (USD $)	Sep. 30, 2013	Sep. 30, 2012	Mar. 15, 2011	Apr. 30, 2012 Institutional Investor [Member] Common Stock [Member]	Mar. 31, 2013 Series A Warrants [Member]	Apr. 30, 2012 Series A Warrants [Member] Institutional Investor [Member]	Apr. 09, 2012 Series A Warrants [Member] Institutional Investor [Member]	Oct. 31, 2012 Series B Warrants [Member]	Sep. 30, 2012 Series B Warrants [Member]	Oct. 31, 2012 Series B Warrants [Member]	Apr. 30, 2012 Series B Warrants [Member] Institutional Investor [Member]	Apr. 09, 2012 Series B Warrants [Member] Institutional Investor [Member]	Mar. 31, 2011 Deerfield Warrant [Member]	Mar. 31, 2013 Deerfield Warrant [Member]	Sep. 30, 2013 Deerfield Warrant [Member]	Apr. 30, 2012 Deerfield Warrant [Member]	Mar. 15, 2011 Deerfield Warrant [Member]
Warrants to Purchase Common Stock Shares						6,517,648					6,517,648		6,000,000
Class of Warrant or Right, Exercise Price of Warrants or Rights			1.57				1.15	0.85		0.85		0.85				1.25	1.57
Debt Instrument, Increase (Decrease), Net, Total														$ 7,500,000
Stock Issued During Period Shares Private Placement				6,517,648
Class of Warrant or Right, Date from which Warrants or Rights Exercisable															Mar. 15, 2017
Class of Warrant or Right Exercised During Period					1,109,010			4,627,941	1,133,824	5,761,765				6,000,000
Proceeds from Warrant Exercises	$ 1,275,000	$ 963,000			$ 1,275,000			$ 3,934,000	$ 964,000
Class Of Warrant Or Right Subject To Expiry					5,408,638
Investment Warrants Expiration Date					Apr. 30, 2018					Oct. 31, 2012
Class Of Warrant Or Right Expiry Term						six-year					six-month
Class Of Warrant Or Right Expired During Period										755,883