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Organization and Basis of Presentation. (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Organization and Basis of Presentation. (Details) [Line Items] |  |  |  |
Operating annual production, description |  | As of September 30, 2021, the Company was operating at approximately 71% of its 410 million gallon annual production capacity. |  |
Accounts receivable balance | $ 59,997,000 | $ 59,997,000 |  | $ 35,839,000
Allowance for doubtful accounts | 360,000 | 360,000 |  | $ 260,000
Bad debt expense |  | 140,000 | $ 1,000 |
Debt [Member] |  |  |  |
Organization and Basis of Presentation. (Details) [Line Items] |  |  |  |
Bad debt expense | $ 3,000 | $ 140,000 |  |

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