Common Stock	12 Months Ended
Dec. 31, 2019
Equity [Abstract]
Common Stock	Common Stock Public Offering On December 6, 2019, the Company completed an underwritten public offering in which it sold 6,250,000 shares of its common stock at a public offering price of $4.00 per share, and it sold to certain investors pre-funded warrants to purchase 3,750,000 shares of its common stock at a public offering price of $3.999 per share underlying each warrant. The offering included an option for the underwriters to purchase up to an additional 1,500,000 shares of its common stock, which was subsequently exercised in full by the underwriters. The shares of its common stock were sold to the underwriters at a purchase price of $3.736 per share and the pre-funded warrants were sold to the underwriters at a purchase price of $3.735 per share underlying each warrant. The pre-funded warrants are immediately exercisable with certain restrictions and do not expire. The net proceeds from the offering, after deducting underwriting discounts and commissions of $3.0 million and other offering expenses of $0.4 million, was approximately $42.6 million. The Company evaluated the pre-funded warrants for liability or equity classification in accordance with the provisions of ASC 480, Distinguishing Liabilities from Equity, and ASC 815-40, Derivatives and Hedging. Based on the provisions governing the pre-funded warrants in the applicable agreement, the Company determined that the pre-funded warrants meet the criteria required to be classified as an equity award subject to the guidance in ASC 815-10 and 815-40 and should effectively be treated as outstanding common shares in both basic and diluted EPS calculations. miniCEP290 Program - University of Massachusetts On July 22, 2019, the Company entered into its exclusive license agreement with the University of Massachusetts ("UMass") for rights to its miniCEP290 program (the "miniCEP290 License Agreement"). Pursuant to the terms of the miniCEP290 License Agreement, the Company issued to UMass 75,000 shares of the Company's common stock, which were valued at approximately $0.1 million. Based on and relying on certain representations made by UMass, the Company issued those shares pursuant to an exemption from registration afforded by Section 4(a)(2) of the Securities Act of 1933, as amended (the "Securities Act").

Common Stock

Public Offering

On December 6, 2019, the Company completed an underwritten public offering in which it sold 6,250,000 shares of its common stock at a public offering price of $4.00 per share, and it sold to certain investors pre-funded warrants to purchase 3,750,000 shares of its common stock at a public offering price of $3.999 per share underlying each warrant. The offering included an option for the underwriters to purchase up to an additional 1,500,000 shares of its common stock, which was subsequently exercised in full by the underwriters. The shares of its common stock were sold to the underwriters at a purchase price of $3.736 per share and the pre-funded warrants were sold to the underwriters at a purchase price of $3.735 per share underlying each warrant. The pre-funded warrants are immediately exercisable with certain restrictions and do not expire.

The net proceeds from the offering, after deducting underwriting discounts and commissions of $3.0 million and other offering expenses of $0.4 million, was approximately $42.6 million.

The Company evaluated the pre-funded warrants for liability or equity classification in accordance with the provisions of ASC 480, Distinguishing Liabilities from Equity, and ASC 815-40, Derivatives and Hedging. Based on the provisions governing the pre-funded warrants in the applicable agreement, the Company determined that the pre-funded warrants meet the criteria required to be classified as an equity award subject to the guidance in ASC 815-10 and 815-40 and should effectively be treated as outstanding common shares in both basic and diluted EPS calculations.

miniCEP290 Program - University of Massachusetts

On July 22, 2019, the Company entered into its exclusive license agreement with the University of Massachusetts ("UMass") for rights to its miniCEP290 program (the "miniCEP290 License Agreement"). Pursuant to the terms of the miniCEP290 License Agreement, the Company issued to UMass 75,000 shares of the Company's common stock, which were valued at approximately $0.1 million. Based on and relying on certain representations made by UMass, the Company issued those shares pursuant to an exemption from registration afforded by Section 4(a)(2) of the Securities Act of 1933, as amended (the "Securities Act").