Common Stock Warrant Liability	6 Months Ended
Jun. 30, 2016
Disclosure Common Stock Warrants Additional Informational [Abstract]
Common Stock Warrant Liability	Common Stock Warrant Liability In July 2012, in connection with a public offering of common stock and warrants, the Company sold warrants to purchase 1,973,025 shares of common stock (including over-allotment purchase) and at June 30, 2016, warrants to purchase 1,901,918 shares of common stock are outstanding. The warrants are exercisable at an exercise price of $20.00 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). None of these warrants were exercised during the three or six months ended June 30, 2016 or the year ended December 31, 2015. The fair value of the warrants outstanding was approximately $643,000 and $6,069,000 as of June 30, 2016 and December 31, 2015, respectively. In July 2011, upon the closing of and in connection with the Healthcare Royalty financing agreement, the Company issued a warrant to Healthcare Royalty exercisable into 28,125 shares of common stock. The warrant is exercisable at $72.00 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 $49,000 and $127,000 as of June 30, 2016 and December 31, 2015, respectively.

Common Stock Warrant Liability

In July 2012, in connection with a public offering of common stock and warrants, the Company sold warrants to purchase 1,973,025 shares of common stock (including over-allotment purchase) and at June 30, 2016, warrants to purchase 1,901,918 shares of common stock are outstanding. The warrants are exercisable at an exercise price of $20.00 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). None of these warrants were exercised during the three or six months ended June 30, 2016 or the year ended December 31, 2015. The fair value of the warrants outstanding was approximately $643,000 and $6,069,000 as of June 30, 2016 and December 31, 2015, respectively.

In July 2011, upon the closing of and in connection with the Healthcare Royalty financing agreement, the Company issued a warrant to Healthcare Royalty exercisable into 28,125 shares of common stock. The warrant is exercisable at $72.00 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 $49,000 and $127,000 as of June 30, 2016 and December 31, 2015, respectively.