Stockholders' Equity
 9 Months Ended
Sep. 30, 2016
Equity [Abstract]  
Stockholders' Equity
Stockholders' Equity
On May 15, 2015, the Company entered into a sales agreement (the “Sales Agreement”) with Cowen and Company, LLC (“Cowen”), pursuant to which the Company may issue and sell shares of its common stock having aggregate sales proceeds of up to $25.0 million from time to time through an “at the market” equity program under which Cowen acts as sales agent.
During the nine months ended September 30, 2016, the Company sold an aggregate of 2,340,980 shares of common stock under the Sales Agreement, at an average price of approximately $2.68 per share, for gross proceeds of $6.3 million and net proceeds of $6.0 million after deducting commissions and other transactions costs. During the nine months ended September 30, 2015, proceeds from issuance of common stock under the Sales Agreement were $2.5 million after deducting commissions and other transaction costs.
As of September 30, 2016, $15.0 million of common stock remained available to be sold under the Sales Agreement, subject to certain conditions specified therein.
In September 2016, the Company issued 15,753 shares of common stock pursuant to the cashless exercise of certain warrants at an exercise price of $0.67 price per share.