Stockholders' Equity (Deficit)	9 Months Ended
Sep. 30, 2020
Equity [Abstract]
Stockholders' Equity (Deficit)	7. Stockholders’ Equity (Deficit) Equity Distribution Agreement On July 30, 2019, the Company entered into the Sales Agreement with Canaccord, as agent, pursuant to which the Company may offer and sell shares of common stock, for aggregate gross sale proceeds of up to $30.0 million from time to time through Canaccord. On March 9, 2020, the Company entered into an amendment to the Sales Agreement to increase the aggregate gross sales amount from $30.0 million to $65.0 million. On April 8, 2020, the Company entered into an amendment to the Sales Agreement to increase the aggregate gross sales amount from $65.0 million to $95.0 million. As of September 30, 2020, the Company had sold 101,606,667 shares of common stock with an aggregate gross sales amount of $95.0 million. Upon delivery of a placement notice based on the Company’s instructions and subject to the terms and conditions of the Sales Agreement, Canaccord was able to sell the shares by methods deemed to be an “at the market” offering, subject to shelf limitations if any, in negotiated transactions at market prices prevailing at the time of sale or at prices related to such prevailing market prices, or by any other method permitted by law, including negotiated transactions, subject to the prior written consent of the Company. The Company was not obligated to make any sales of shares under the Sales Agreement. The Company or Canaccord were able to suspend or terminate the offering of shares upon notice to the other party, subject to certain conditions. Canaccord acted as sales agent on a commercially reasonable efforts basis consistent with its normal trading and sales practices and applicable state and federal law, rules and regulations and the rules of Nasdaq. The Company had agreed to pay Canaccord for its services of acting as agent an amount equal to 3% of the gross proceeds from the sale of the shares pursuant to the Sales Agreement. The Company had also agreed to provide Canaccord with customary indemnification for certain liabilities. Legal and accounting fees were changed to share capital upon issuance of shares under the Sales Agreement. During the nine months ended September 30, 2020, the Company sold 96,120,167 shares under the Sales Agreement for net proceeds of $85.0 million after expenses. Purchase Agreement On July 29, 2019, the Company entered into a $30.0 million Purchase Agreement with Lincoln Park, pursuant to which the Company was able to sell and issue to Lincoln Park, and Lincoln Park was obligated to purchase, up to $30.0 million in value of its shares of common stock from time to time over a 36-month period starting from the effective date of the respective registration statement. On April 7, 2020, the Company terminated the Purchase Agreement, effective April 8, 2020. The Company was able to direct Lincoln Park, at its sole discretion, and subject to certain conditions, to purchase up to 200,000 shares of common stock on any business day, provided that at least one business day had passed since the most recent purchase. The amount of a purchase could be increased under certain circumstances provided, however, that Lincoln Park’s committed obligation under any single purchase would not exceed $2.0 million. The purchase price of shares of common stock related to the future funding was based on the then prevailing market prices of such shares at the time of sales as described in the Purchase Agreement. In consideration for the execution and delivery of the Purchase Agreement, the Company issued 413,349 shares of common stock to Lincoln Park. During the nine months ended September 30, 2020, the Company sold 400,000 shares for proceeds of $0.3 million in connection with the Purchase Agreement.

Stockholders' Equity (Deficit)

9 Months Ended

Sep. 30, 2020

7. Stockholders’ Equity (Deficit)

Equity Distribution Agreement

On July 30, 2019, the Company entered into the Sales Agreement with Canaccord, as agent, pursuant to which the Company may offer and sell shares of common stock, for aggregate gross sale proceeds of up to $30.0 million from time to time through Canaccord. On March 9, 2020, the Company entered into an amendment to the Sales Agreement to increase the aggregate gross sales amount from $30.0 million to $65.0 million. On April 8, 2020, the Company entered into an amendment to the Sales Agreement to increase the aggregate gross sales amount from $65.0 million to $95.0 million. As of September 30, 2020, the Company had sold 101,606,667 shares of common stock with an aggregate gross sales amount of $95.0 million.

Upon delivery of a placement notice based on the Company’s instructions and subject to the terms and conditions of the Sales Agreement, Canaccord was able to sell the shares by methods deemed to be an “at the market” offering, subject to shelf limitations if any, in negotiated transactions at market prices prevailing at the time of sale or at prices related to such prevailing market prices, or by any other method permitted by law, including negotiated transactions, subject to the prior written consent of the Company. The Company was not obligated to make any sales of shares under the Sales Agreement. The Company or Canaccord were able to suspend or terminate the offering of shares upon notice to the other party, subject to certain conditions. Canaccord acted as sales agent on a commercially reasonable efforts basis consistent with its normal trading and sales practices and applicable state and federal law, rules and regulations and the rules of Nasdaq.

The Company had agreed to pay Canaccord for its services of acting as agent an amount equal to 3% of the gross proceeds from the sale of the shares pursuant to the Sales Agreement. The Company had also agreed to provide Canaccord with customary indemnification for certain liabilities. Legal and accounting fees were changed to share capital upon issuance of shares under the Sales Agreement.

During the nine months ended September 30, 2020, the Company sold 96,120,167 shares under the Sales Agreement for net proceeds of $85.0 million after expenses.

Purchase Agreement

On July 29, 2019, the Company entered into a $30.0 million Purchase Agreement with Lincoln Park, pursuant to which the Company was able to sell and issue to Lincoln Park, and Lincoln Park was obligated to purchase, up to $30.0 million in value of its shares of common stock from time to time over a 36-month period starting from the effective date of the respective registration statement. On April 7, 2020, the Company terminated the Purchase Agreement, effective April 8, 2020.

The Company was able to direct Lincoln Park, at its sole discretion, and subject to certain conditions, to purchase up to 200,000 shares of common stock on any business day, provided that at least one business day had passed since the most recent purchase. The amount of a purchase could be increased under certain circumstances provided, however, that Lincoln Park’s committed obligation under any single purchase would not exceed $2.0 million. The purchase price of shares of common stock related to the future funding was based on the then prevailing market prices of such shares at the time of sales as described in the Purchase Agreement.

In consideration for the execution and delivery of the Purchase Agreement, the Company issued 413,349 shares of common stock to Lincoln Park.

During the nine months ended September 30, 2020, the Company sold 400,000 shares for proceeds of $0.3 million in connection with the Purchase Agreement.