Common Stock Warrants	3 Months Ended
Mar. 31, 2015
Disclosure Common Stock Warrants Additional Informational [Abstract]
Common Stock Warrants	Common Stock Warrants In July 2012, in connection with a public offering of common stock and warrants, the Company sold warrants to purchase 15,784,200 shares of common stock (including over-allotment purchase). The warrants are exercisable at an exercise price of $2.50 per share and will expire on July 27, 2017, which is five years from the date of issuance. As the warrants contain a cash settlement feature upon the occurrence of certain events that may be outside of the Company’s control, the warrants are recorded as a current liability and are marked to market at each reporting period (see Note 2). During the three months ended March 31, 2015, no warrants to purchase shares of common stock were exercised, and during the year ended December 31, 2014, warrants to purchase 465,250 shares of common stock were exercised. The Company recognized $0 and $1,163,000 in proceeds from the exercise of warrants during the three months ended March 31, 2015 and during the year ended December 31, 2014, respectively. The fair value of the warrants outstanding was approximately $4,585,000 and $4,978,000 as of March 31, 2015 and December 31, 2014, respectively. In July 2011, upon the closing of and in connection with the Healthcare Royalty financing agreement, the Company issued to Healthcare Royalty a warrant exercisable into 225,000 shares of common stock. The warrant is exercisable at $9.00 per share of common stock and has a term of ten years. As the warrant contains covenants where compliance with such covenants may be outside of the Company’s control, the warrant was recorded as a current liability and is marked to market at each reporting date (see Note 2). The fair value of the warrant was approximately $98,000 and $115,000 as of March 31, 2015 and December 31, 2014, respectively.

Common Stock Warrants

In July 2012, in connection with a public offering of common stock and warrants, the Company sold warrants to purchase 15,784,200 shares of common stock (including over-allotment purchase). The warrants are exercisable at an exercise price of $2.50 per share and will expire on July 27, 2017, which is five years from the date of issuance. As the warrants contain a cash settlement feature upon the occurrence of certain events that may be outside of the Company’s control, the warrants are recorded as a current liability and are marked to market at each reporting period (see Note 2). During the three months ended March 31, 2015, no warrants to purchase shares of common stock were exercised, and during the year ended December 31, 2014, warrants to purchase 465,250 shares of common stock were exercised. The Company recognized $0 and $1,163,000 in proceeds from the exercise of warrants during the three months ended March 31, 2015 and during the year ended December 31, 2014, respectively. The fair value of the warrants outstanding was approximately $4,585,000 and $4,978,000 as of March 31, 2015 and December 31, 2014, respectively.

In July 2011, upon the closing of and in connection with the Healthcare Royalty financing agreement, the Company issued to Healthcare Royalty a warrant exercisable into 225,000 shares of common stock. The warrant is exercisable at $9.00 per share of common stock and has a term of ten years. As the warrant contains covenants where compliance with such covenants may be outside of the Company’s control, the warrant was recorded as a current liability and is marked to market at each reporting date (see Note 2). The fair value of the warrant was approximately $98,000 and $115,000 as of March 31, 2015 and December 31, 2014, respectively.