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Stockholders' Equity (Details Narrative) - USD ($) |  |  |  |  | 1 Months Ended | 2 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 22, 2020 | Feb. 27, 2020 | Dec. 04, 2018 | Aug. 31, 2018 | Sep. 30, 2018 | Mar. 05, 2020 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2018 | Mar. 12, 2020
Shelf registration statement amount |  |  |  |  | $ 75,000,000 |  |  |  |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  | $ 18,182,599 | $ 4,464,060 |  |  |
Warrants exercise price |  |  |  |  |  |  | $ 0.01 |  |  |  |
2019 Aspire Purchase Agreements [Member] |  |  |  |  |  |  |  |  |  |  |
Aggregate offering price, additions |  |  |  | $ 15,000,000 |  |  |  |  | $ 10,000,000 |  |
Aggregate offering price, term |  |  |  | 24 months |  |  |  |  | 24 months |  |
Stock issued during period, shares, new issues |  |  |  |  |  | 1,000,000 |  |  | 500,000 |  |
Proceeds from issuance of common stock |  |  |  |  |  | $ 1,600,000 |  |  | $ 700,000 |  |
2018 Aspire Purchase Agreements [Member] |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  |  |  | 3,300,000 | 100,000 |
Proceeds from issuance of common stock |  |  |  |  |  |  |  |  | $ 6,300,000 | $ 200,000 |
Capital on DemandTM Sales Agreement [Member] |  |  |  |  |  |  |  |  |  |  |
Aggregate offering price |  |  | $ 16,000,000 |  |  |  |  |  |  |  |
Capital on Demand Agreement [Member] |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  | 1,200,000 |  | 500,000 |  |
Proceeds from issuance of common stock |  |  |  |  |  |  | $ 3,500,000 |  | $ 1,000,000 |  |
Aggregate value available for issuance |  |  |  |  |  |  | $ 11,500,000 |  |  |  |
Securities Purchase Agreement [Member] |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  | 4,571,428 |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock |  | $ 4,800,000 |  |  |  |  |  |  |  |  |
Shares issued, price per share |  | $ 1.05 |  |  |  |  |  |  |  |  |
Securities Purchase Agreement [Member] | Original Warrants [Member] |  |  |  |  |  |  |  |  |  |  |
Number of warrants to purchase common stock |  | 2,971,428 |  |  |  |  |  |  |  |  |
Warrants term |  | 5 years |  |  |  |  |  |  |  |  |
Warrants exercise price |  | $ 1.15 |  |  |  |  |  |  |  |  |
Private Exchange Agreements [Member] | Warrant [Member] |  |  |  |  |  |  |  |  |  |  |
Number of warrants to purchase common stock |  |  |  |  |  |  |  |  |  |  | 3,200,000
Warrants term |  |  |  |  |  |  |  |  |  |  | 5 years
Warrants exercise price |  |  |  |  |  |  |  |  |  |  | $ 1.24
Underwriting Agreement [Member] | Underwritten Offering [Member] |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues | 2,666,667 |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock | $ 9,100,000 |  |  |  |  |  |  |  |  |  |
Shares issued, price per share | $ 3.75 |  |  |  |  |  |  |  |  |  |
Shares purchased, price per share | 3.4875 |  |  |  |  |  |  |  |  |  |
Underwriting discount price per share | $ 0.2625 |  |  |  |  |  |  |  |  |  |
Percentage of underwriting discount on public offering price | 0.70% |  |  |  |  |  |  |  |  |  |

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