Equity (Details Textual) - USD ($) |
1 Months Ended | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|---|
Apr. 30, 2019 |
Oct. 31, 2018 |
Mar. 31, 2018 |
Sep. 30, 2019 |
Sep. 30, 2018 |
|
| Equity (Textual) | |||||
| Sales of common stock, shares | 42,900,000 | 30,200,000 | 2,800,000 | ||
| Net proceeds on sale of common stock | $ 15,100,000 | $ 13,800,000 | $ 800,000 | ||
| Common shares for consulting services, shares | 400,000 | ||||
| Net proceeds on exercise of warrants | $ 1,503,762 | $ 4,849 | |||
| Description of shares | The Company sold 42.9 million shares of common stock at an offering price of $0.385 per share and warrants to purchase up to 42.9 million shares of common stock at an exercise price of $0.50 per share and with a term of 5 years, resulting in gross proceeds of $16.5 million and net proceeds of $15.1 million after deducting underwriting and other offering expenses. | In March 2018, the Company sold an aggregate of 30.2 million units consisting of an aggregate of 30.2 million shares of common stock, 7.6 million series A warrants and 22.7 million series B warrants, with each series A warrant exercisable for one share of Common Stock at an exercise price of $0.60 per share and each series B warrant exercisable for one share of Common Stock at an exercise price of $0.70 per share, resulting in gross proceeds of approximately $15.1 million (each unit was sold at $0.50 per unit), and net proceeds of approximately $13.8 million after deducting expenses relating to dealer-manager fees and other offering expenses. | |||
| Stock Options [Member] | |||||
| Equity (Textual) | |||||
| Stock option granted to employees | 5,738,500 | ||||
| Option exercise price minimum | $ 0.223 | ||||
| Option exercise price maximum | $ 0.58 | ||||
| Warrants, description | The options have an aggregated fair value of $1.1 million that was calculated using the Black-Scholes option-pricing model. Variables used in the Black-Scholes option-pricing model include: (1) discount rate range from 1.38% to 2.60% (2) expected life of 6 years, (3) expected volatility range from 78.5% to 80.6%, and (4) no expected dividends. During the nine months ended September 30, 2019, options to purchase 1.0 million shares were cancelled upon the termination of employment for several employees. | ||||
| Total option expense | $ 900,000 | 1,300,000 | |||
| Unrecognized compensation expense | $ 2,500,000 | ||||
| Number of stock options canceled | 1,042,800 | ||||
| Stock options, term | 10 years | ||||
| Stock options, vesting period | 4 years | ||||
| Lincoln Park Capital Fund, LLC [Member] | |||||
| Equity (Textual) | |||||
| Received amount | $ 100,000 | ||||
| Sales of common stock, shares | 400,000 | ||||
| Number of shares of restricted stock, vested | 100,000 | ||||
| Lincoln Park Capital Fund, LLC [Member] | Purchase Agreement [Member] | |||||
| Equity (Textual) | |||||
| Net proceeds on sale of common stock | $ 32,500,000 | ||||
| Warrants [Member] | |||||
| Equity (Textual) | |||||
| Warrants, description | The transaction date relative fair value of the April 2019 warrants of $5.3 million was determined utilizing the Black-Scholes option pricing model and variables of (1) a discount rate of 2.35%, (2) expected term of 5 years, (3) expected volatility of 78% and (4) zero expected dividends. | ||||
| Description of warrants | The Company has outstanding warrants to purchase 57,212 shares that include down-round protection. For warrants with down-round protection, a deemed dividend is recorded for the change in fair value of the warrants when the down-round provision is triggered. As result of the April 2019 offering, the exercise price of the warrant was reset from $1.25 per share to $0.88 per share. The down-round protection provision in the above warrants created a deemed dividend to common stockholders of $1,269, which is reflected in the accompanying consolidated statement of operations and consolidated statement of changes in stockholders' equity. | ||||
| Series A warrants [Member] | |||||
| Equity (Textual) | |||||
| Sales of common stock, shares | 30,200,000 | ||||
| Issuance of common stock, shares | 30,200,000 | ||||
| Warrants exercised by warrant holders | 2,500,000 | ||||
| Weighted average remaining contractual term | 3 years 4 months 24 days | ||||
| Series B warrants [Member] | |||||
| Equity (Textual) | |||||
| Description of warrant exercisable | Each series B warrant exercisable for one share of Common Stock at an exercise price of $0.70 per share. | ||||
| Aggregate series warrants | 22,700,000 | ||||