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Financial Condition and Business Plan (Details Narrative) - USD ($) |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
May 10, 2021 | Mar. 19, 2021 | Aug. 28, 2020 | Jan. 31, 2021 | Sep. 30, 2020 | Jun. 30, 2018 | Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2020
Cumulated net losses |  |  |  |  |  |  | $ (317,689,344) |  |  |  | $ (312,000,341)
Cash and cash equivalents, short-term investments and receivable on sale of net operating losses |  |  |  |  |  |  | 54,600,000 |  |  |  |
Receivable on sale of net operating losses |  |  |  |  |  |  | 1,845,823 |  |  |  |
Proceeds from warrant exercises |  |  |  |  |  |  | 1,508,666 |  |  |  |
Proceeds from sale of equity |  |  |  |  |  |  | $ 15,000,000 |  |  |  |
Horizon Credit Agreement [Member] | Horizon Technology Finance Corporation [Member] |  |  |  |  |  |  |  |  |  |  |
Proceeds from new capital |  |  |  |  |  | $ 10,000,000 |  |  |  |  |
Debt instrument face amount |  |  | $ 10,000,000 |  |  |  |  |  |  |  |
Horizon Credit Agreement [Member] | Horizon Technology Finance Corporation [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate |  |  |  |  |  | 7.625% |  |  |  |  |
Amendment to Horizon Credit Agreement [Member] | Horizon Technology Finance Corporation [Member] |  |  |  |  |  |  |  |  |  |  |
Repayment of loans |  |  | 5,000,000 |  |  |  |  |  |  |  |
Debt instrument face amount |  |  | 5,000,000 |  |  |  |  |  |  |  |
Debt instrument related end term charges |  |  | $ 200,000 |  |  |  |  |  |  |  |
Capital on DemandTM Sales Agreement [Member] | Jones Trading Institutional Services, LLC [Member] |  |  |  |  |  |  |  |  |  |  |
Proceeds from new capital |  | $ 6,900,000 |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  | $ 35,000,000 |  |  |  |  |  |  |
Proceeds from warrant exercises |  |  |  | $ 1,500,000 |  |  |  |  |  |  |
New Jersey [Member] |  |  |  |  |  |  |  |  |  |  |
Net proceeds from sale of net operating losses |  |  |  |  | $ 2,000,000 |  |  |  | $ 12,200,000 | $ 13,000,000 |
New Jersey [Member] | Subsequent Event [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Net proceeds from sale of net operating losses | $ 15,000,000 |  |  |  |  |  |  |  |  |  |
New Jersey [Member] | Subsequent Event [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Net proceeds from sale of net operating losses | $ 20,000,000 |  |  |  |  |  |  |  |  |  |

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