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STOCKHOLDERS' EQUITY (Common Stock, 2018 Purchase Agreement and LP Purchase Agreement) (Details) - USD ($) |  | 3 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Mar. 26, 2020 | Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2021 | Dec. 20, 2018 | Dec. 19, 2018
Class of Stock [Line Items] |  |  |  |  |  |
Common stock, shares authorized (in shares) |  | 150,000,000 |  | 150,000,000 | 250,000,000 | 150,000,000
Warrant exercises in period |  |  | 0 |  |  |
Shares issued (in shares) |  | 22,708,708 |  | 22,708,442 |  |
Common stock, shares outstanding (in shares) |  | 22,708,708 |  | 22,708,442 |  |
Issuance of common stock, net of issuance costs |  |  | $ 1,260,000 |  |  |
Issuance of common stock for consulting services |  |  | $ 150,000 |  |  |
Common Stock [Member] |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Proceeds upon issuance of common stock from exercise of warrants (in shares) |  | 266 |  |  |  |
Warrant exercises in period |  | 266 |  |  |  |
Issuance of common stock for consulting services (in shares) |  |  | 55,147 |  |  |
Issuance of common stock for consulting services |  |  | $ 200,000 |  |  |
Common Stock [Member] |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Proceeds upon issuance of common stock from exercise of warrants (in shares) |  | 266 |  |  |  |
Preferred Class B |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Conversion price (in dollars per share) |  | $ 0.40 |  |  |  |
Lincoln Park [Member] |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Shares sold in offering (in shares) |  |  | 500,000 |  |  |
Issuance of common stock, net of issuance costs |  |  | $ 1,300,000 |  |  |
Maximum [Member] | Common Stock [Member] |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Proceeds from exercise of warrants |  | $ 1,000 |  |  |  |
LP 2020 Purchase Agreement [Member] | Lincoln Park [Member] |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Issuance of common stock in connection with at the market offering, net of issuance costs | $ 10,000,000 |  |  |  |  |

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