Equity (Details) - USD ($) |
1 Months Ended | 12 Months Ended | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Mar. 14, 2017 |
Aug. 31, 2020 |
Jul. 19, 2020 |
Jun. 19, 2020 |
Apr. 24, 2020 |
Apr. 30, 2019 |
Oct. 31, 2018 |
Mar. 31, 2018 |
Sep. 30, 2013 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Nov. 18, 2020 |
Apr. 30, 2020 |
Jun. 30, 2019 |
Dec. 31, 2013 |
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Equity (Details) [Line Items] | |||||||||||||||
Description of shares | the Company issued and sold 4.3 million shares of common stock and 2.8 million pre-funded warrants to purchase shares of common stock. The price to the public in this offering for each share of common stock was $4.50 and for each pre-funded warrant was $4.497. Each pre-funded warrant had an exercise price of $0.003 per share and was exercisable immediately upon issuance. Gross proceeds from this offering were $31.6 million, before deducting underwriting discounts and commissions and other offering expenses payable by the Company. Net proceeds from this offering were $29.1 million. | ||||||||||||||
Sale of common stock | 1,400,000 | ||||||||||||||
Exercise price of warrants (in Dollars per share) | $ 15.00 | $ 26.40 | $ 15.61515 | ||||||||||||
Warrant to purchase of common stock | 1,907 | 1,400,000 | |||||||||||||
Gross proceeds (in Dollars) | $ 16,500,000 | $ 22,600,000 | |||||||||||||
Net proceeds (in Dollars) | $ 15,100,000 | ||||||||||||||
Equity description | the Company entered into the Capital on Demand™ Sales Agreement with JonesTrading Institutional Services LLC (“JonesTrading”), pursuant to which the Company may sell, from time to time, through or to JonesTrading, up to an aggregate of $200 million of its common stock. Shares of common stock are offered pursuant to the Company’s shelf registration statement on Form S-3 filed with the SEC on August 7, 2020. | ||||||||||||||
Sale of common stock, shares | 2,100,000 | 93,000 | |||||||||||||
Net proceeds on sale of common stock (in Dollars) | $ 21,700,000 | $ 700,000 | |||||||||||||
Offering price (in Dollars per share) | $ 11.55 | ||||||||||||||
Discount rate | 2.35% | ||||||||||||||
Expected term | 5 years | ||||||||||||||
Expected volatility | 78.00% | ||||||||||||||
Expected dividends | 0.00% | ||||||||||||||
Sale of stock, description | the Company sold an aggregate of 1.0 million units consisting of an aggregate of 1.0 million shares of common stock, 0.3 million series A warrants and 0.8 million series B warrants, with each series A warrant exercisable for one share of common stock at an exercise price of $18.00 per share and each series B warrant exercisable for one share of common stock at an exercise price of $21.00 per share. During the year ended December 31, 2019, holders of March 2018 series A warrants exercised 84 thousand shares, resulting in the Company receiving $1.5 million. The remaining March 2018 series A warrants expired in March 2019. The March 2018 Series B warrants expired in September 2020. | ||||||||||||||
Deemed dividend (in Dollars) | 1,000 | 1 | |||||||||||||
Stock-based compensation expense (in Dollars) | $ 13,000 | $ 8,000 | |||||||||||||
Equity Option [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Stock option granted | 458,000 | 195,000 | |||||||||||||
Option exercise price minimum (in Dollars per share) | $ 6.63 | $ 6.44 | |||||||||||||
Option exercise price maximum (in Dollars per share) | $ 12.41 | $ 17.40 | |||||||||||||
Stock options, term | 10 years | 10 years | |||||||||||||
Aggregated fair value (in Dollars) | $ 3,200,000 | $ 1,100,000 | |||||||||||||
Stock option, description | Variables used in the Black-Scholes option-pricing model include: (1) discount rate range from 0.34% to 0.56% (2) expected life of 6 years, (3) expected volatility range from 83.6% to 85.5%, and (4) zero expected dividends. | Variables used in the Black-Scholes option-pricing model include: (1) discount rate range from 1.38% to 2.6% (2) expected life of 6 years, (3) expected volatility range from 78.5% to 81.8%, and (4) zero expected dividends. | |||||||||||||
Number of options, shares cancelled | 23,000 | 56,000 | |||||||||||||
Unvested options (in Dollars) | $ 4,000,000 | ||||||||||||||
weighted average Term | 3 years 109 days | ||||||||||||||
Total option expense (in Dollars) | $ 1,200,000 | $ 1,200,000 | |||||||||||||
Minimum [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Exercise price of warrants (in Dollars per share) | $ 26.40 | ||||||||||||||
Minimum [Member] | Equity Option [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Vesting period | 4 years | 4 years | |||||||||||||
Maximum [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Exercise price of warrants (in Dollars per share) | $ 37.50 | ||||||||||||||
Maximum [Member] | Equity Option [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Vesting period | 4 years 73 days | 4 years 73 days | |||||||||||||
Lincoln Park Capital Fund, LLC [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Sale of common stock, shares | 27,000 | 13,000 | |||||||||||||
Aggregate value of common stock, shares over life of agreement (in Dollars) | $ 32,500,000 | ||||||||||||||
Received amount (in Dollars) | $ 200,000 | $ 100,000 | |||||||||||||
2019 Amended and Restated Stock Plan [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Number of shares authorized | 333,333 | ||||||||||||||
Total number of shares of common stock available for grant | 3,083,333 | ||||||||||||||
Plan expiration date | Oct. 18, 2029 | ||||||||||||||
2013 Amended and Restated Stock Plan [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Number of shares authorized | 91,666 | ||||||||||||||
Total number of shares of common stock available for grant | 758,333 | ||||||||||||||
Plan expiration date | Sep. 09, 2023 | ||||||||||||||
2013 Equity Incentive Plan [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Number of shares authorized | 15,000 | ||||||||||||||
Total number of shares of common stock available for grant | 33,333 | ||||||||||||||
Plan expiration date | Sep. 09, 2023 | ||||||||||||||
Warrant [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Sale of common stock | 1,900,000 | 1,400,000 | 2,800,000 | ||||||||||||
Exercise price of warrants (in Dollars per share) | $ 0.003 | $ 15.00 | $ 0.003 | ||||||||||||
Warrant to purchase of common stock | 700,000 | 1,400,000 | 2,800,000 | ||||||||||||
Share price (in Dollars per share) | $ 9.75 | ||||||||||||||
Pre-funded warrant per share (in Dollars per share) | $ 9.747 | ||||||||||||||
Gross proceeds (in Dollars) | $ 25,000,000 | ||||||||||||||
Net proceeds (in Dollars) | $ 23,000,000 | ||||||||||||||
Offering price (in Dollars per share) | $ 11.55 | ||||||||||||||
Aggregated fair value (in Dollars) | $ 5,300,000 | ||||||||||||||
Warrant term | 5 years | ||||||||||||||
Sale of stock, description | the Company sold an aggregate of 1.0 million units consisting of an aggregate of 1.0 million shares of common stock, 0.3 million series A warrants and 0.8 million series B warrants, with each series A warrant exercisable for one share of common stock at an exercise price of $18.00 per share and each series B warrant exercisable for one share of common stock at an exercise price of $21.00 per share. During the year ended December 31, 2019, holders of March 2018 series A warrants exercised 84 thousand shares, resulting in the Company receiving $1.5 million. The remaining March 2018 series A warrants expired in March 2019. The March 2018 Series B warrants expired in September 2020. | ||||||||||||||
Pre-funded Warrants [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Sale of common stock | 700,000 | ||||||||||||||
Exercise price of warrants (in Dollars per share) | $ 0.003 | ||||||||||||||
Warrant to purchase of common stock | 700,000 | ||||||||||||||
Share price (in Dollars per share) | $ 0.003 | ||||||||||||||
Common Stock [Member] | |||||||||||||||
Equity (Details) [Line Items] | |||||||||||||||
Sale of common stock, shares | 300,000 | ||||||||||||||
Net proceeds on sale of common stock (in Dollars) | $ 2,500,000 |