Common and Preferred Stock	6 Months Ended
Jun. 30, 2021
Equity [Abstract]
Common and Preferred Stock	9. Common and Preferred Stock The Company is authorized to issue 400,000,000 shares of common stock, par value $0.01 per share, and 10,000,000 shares of undesignated preferred stock, par value $0.01 per share, issuable in one or more series as designated by the Company’s board of directors. No other class of capital stock is authorized. As of June 30, 2021 and December 31, 2020, 249,617,550 and 242,117,089 shares of common stock, respectively, were issued and outstanding and no shares of preferred stock were outstanding. In February 2018, the Company entered into a controlled equity offering sales agreement (the “CF Sales Agreement”) with Cantor Fitzgerald & Co. (“Cantor Fitzgerald”), as sales agent, pursuant to which the Company may offer and sell, from time to time, through Cantor Fitzgerald, shares of the Company’s common stock having an aggregate offering price of up to $50.0 million or such other amount as may be permitted by the Sales Agreement. Under the Sales Agreement, Cantor Fitzgerald may sell shares by any method deemed to be an “at-the-market offering” as defined in Rule 415 under the Securities Act of 1933, as amended. For the six months ended June 30, 2021, the Company sold an aggregate of 578,063 shares of the Company’s common stock at a weighted average purchase price of $3.26 per share for an aggregate gross proceeds of approximately $1.9 million pursuant to the Sales Agreement. For the six months ended June 30, 2020, the Company sold an aggregate of 7,871,461 shares of the Company’s common stock at a weighted average purchase price of $1.64 per share for an aggregate gross proceeds of approximately $12.9 million pursuant to the CF Sales Agreement. In the first quarter of 2021, Mann Group converted $0.4 million of interest and $9.6 million of principal into 4,000,000 shares of common stock in accordance with the terms of the Mann Group convertible note. See Note 6 – Borrowings. In February 2021, the Company converted $5.0 million principal amount of 2024 convertible notes into 1,666,667 shares of the Company’s common stock in accordance with the terms of the 2024 convertible notes. See Note 6 – Borrowings. For the three and six months ended June 30, 2021, the Company received $0.1 million from the market price stock purchase plan for 25,000 shares. There was a de minimis amount of market price stock purchase plan transactions for the three and six months ended June 30, 2020.

Common and Preferred Stock

6 Months Ended

Jun. 30, 2021

9. Common and Preferred Stock

The Company is authorized to issue 400,000,000 shares of common stock, par value $0.01 per share, and 10,000,000 shares of undesignated preferred stock, par value $0.01 per share, issuable in one or more series as designated by the Company’s board of directors. No other class of capital stock is authorized. As of June 30, 2021 and December 31, 2020, 249,617,550 and 242,117,089 shares of common stock, respectively, were issued and outstanding and no shares of preferred stock were outstanding.

In February 2018, the Company entered into a controlled equity offering sales agreement (the “CF Sales Agreement”) with Cantor Fitzgerald & Co. (“Cantor Fitzgerald”), as sales agent, pursuant to which the Company may offer and sell, from time to time, through Cantor Fitzgerald, shares of the Company’s common stock having an aggregate offering price of up to $50.0 million or such other amount as may be permitted by the Sales Agreement. Under the Sales Agreement, Cantor Fitzgerald may sell shares by any method deemed to be an “at-the-market offering” as defined in Rule 415 under the Securities Act of 1933, as amended. For the six months ended June 30, 2021, the Company sold an aggregate of 578,063 shares of the Company’s common stock at a weighted average purchase price of $3.26 per share for an aggregate gross proceeds of approximately $1.9 million pursuant to the Sales Agreement. For the six months ended June 30, 2020, the Company sold an aggregate of 7,871,461 shares of the Company’s common stock at a weighted average purchase price of $1.64 per share for an aggregate gross proceeds of approximately $12.9 million pursuant to the CF Sales Agreement.

In the first quarter of 2021, Mann Group converted $0.4 million of interest and $9.6 million of principal into 4,000,000 shares of common stock in accordance with the terms of the Mann Group convertible note. See Note 6 – Borrowings.

In February 2021, the Company converted $5.0 million principal amount of 2024 convertible notes into 1,666,667 shares of the Company’s common stock in accordance with the terms of the 2024 convertible notes. See Note 6 – Borrowings.

For the three and six months ended June 30, 2021, the Company received $0.1 million from the market price stock purchase plan for 25,000 shares. There was a de minimis amount of market price stock purchase plan transactions for the three and six months ended June 30, 2020.