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Stockholders' Equity (Details Narrative) - USD ($) |  |  |  |  |  |  | 1 Months Ended | 2 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 22, 2021 | Sep. 08, 2020 | Jun. 22, 2020 | Feb. 27, 2020 | Dec. 04, 2018 | Aug. 31, 2018 | Sep. 30, 2018 | Mar. 05, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Sep. 21, 2020 | Mar. 12, 2020
Shelf registration statement amount |  |  |  |  |  |  | $ 75,000,000 |  |  |  |  |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  | $ 22,811,669 | $ 7,844,852 |  |  |
Warrants term |  |  |  |  |  |  |  |  |  |  |  |  | 4 years |
Warrants exercise price |  |  |  |  |  |  |  |  |  | $ 0.01 | $ 0.01 |  | $ 0.79 |
Common Stock Outstanding [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  | 2,666,667 |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock |  |  | $ 9,100,000 |  |  |  |  |  |  |  |  |  |  |
Capital on DemandTM Sales Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate offering price |  |  |  |  | $ 16,000,000 |  |  |  |  |  |  |  |  |
Capital on Demand Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  |  |  |  | 5,200,000 | 500,000 |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  | $ 6,200,000 | $ 1,000,000 |  |  |
Capital on Demand Agreement [Member] | Forecast [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  |  |  | 7,200,000 |  |  |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  |  |  | $ 6,900,000 |  |  |  |  |
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 |  |  |  |  |  |  |  |  |  |
Securities Purchase Agreement [Member] | Forecast [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues | 25,925,925 |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock | $ 35,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued, price per share | $ 1.35 |  |  |  |  |  |  |  |  |  |  |  |  |
Placement agent fee description | The Company agreed to pay the January 2021 Placement Agents a cash fee equal to 7% of the aggregate gross proceeds raised from the sale of the securities sold in the January 2021 Offering and reimburse the January 2021 Placement Agents for certain of their expenses in an amount not to exceed $82,500. |  |  |  |  |  |  |  |  |  |  |  |  |
Exchange Agreements [Member] | Warrant [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants to purchase common stock |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,200,000
Warrants term |  |  |  |  |  |  |  |  |  |  |  |  |  | 5 years
Warrants exercise price |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1.24
Exchange Agreements [Member] | Forecast [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants to purchase common stock |  |  |  |  |  |  |  |  | 1,200,000 |  |  |  |  |
Proceeds from issuance of warrants |  |  |  |  |  |  |  |  | $ 1,500,000 |  |  |  |  |
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% |  |  |  |  |  |  |  |  |  |  |
LPC Purchase Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  |  |  |  | 3,300,000 |  |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  | $ 2,200,000 |  |  |  |
LPC Purchase Agreement [Member] | Lincoln Park Capital Fund, LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  | 26,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Sale of stock, description of transaction |  | Over the 36-month term of the LPC Purchase Agreement, we have the right, but not the obligation, from time to time, in our sole discretion and subject to certain conditions, including that the closing price of our Common Stock is not below $0.25 per share, to direct Lincoln Park to purchase up to an aggregate amount of $26.0 million (subject to certain limitations) of shares of Common Stock. Under the Purchase Agreement, on any business day selected by us, we may direct Lincoln Park to purchase up to 400,000 shares (the "Regular Purchase Share Limit") of our Common Stock (each such purchase, a "Regular Purchase"). Lincoln Park's maximum obligation under any single Regular Purchase will not exceed $1,500,000 unless we mutually agree to increase the maximum amount of such Regular Purchase. |  |  |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership percentage |  | 9.99% |  |  |  |  |  |  |  |  |  |  |  |
LPC Purchase Agreement [Member] | Exchange Cap of Common Stock [Member] | Lincoln Park Capital Fund, LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  | 6,688,588 |  |  |  |  |  |  |  |  |  |  |  |
LPC Purchase Agreement [Member] | LPC Commitment Shares [Member] | Lincoln Park Capital Fund, LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  | 437,828 |  |  |  |  |  |  |  |  |  |  |  |
LPC Purchase Agreement [Member] | Common Stock Outstanding [Member] | Lincoln Park Capital Fund, LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate offering price |  | $ 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  | 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Shares issued, price per share |  | $ 1.00 |  |  |  |  |  |  |  |  |  |  |  |
Regular Purchase Share Limit [Member] | Lincoln Park Capital Fund, LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of stock, description of transaction |  | If we direct Lincoln Park to purchase the maximum number of shares of Common Stock we then may sell in a Regular Purchase, then in addition to such Regular Purchase, and subject to certain conditions and limitations in the LPC Purchase Agreement, we may direct Lincoln Park to make an "accelerated purchase" of an additional amount of Common Stock that may not exceed the lesser of (i) 300% of the number of shares purchased pursuant to the corresponding Regular Purchase and (ii) 30% of the total number of shares of our Common Stock traded on The Nasdaq Capital Market during a specified period on the applicable purchase date as set forth in the Purchase Agreement. Under certain circumstances and in accordance with the Purchase Agreement, the Company may direct Lincoln Park to purchase shares in multiple accelerated purchases on the same trading day. |  |  |  |  |  |  |  |  |  |  |  |
Regular Purchase Share Limit [Member] | Lincoln Park Capital Fund, LLC [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  | 400,000 |  |  |  |  |  |  |  |  |  |  |  |
2019 Aspire Purchase Agreements [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  |  | 1,000,000 |  | 500,000 |  |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  |  | $ 1,600,000 |  | $ 700,000 |  |  |  |
Aggregate offering price, additions |  |  |  |  |  | $ 15,000,000 |  |  |  | $ 10,000,000 |  |  |  |
Aggregate offering price, term |  |  |  |  |  | 24 months |  |  |  | 24 months |  |  |  |
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 |  |

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