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REVENUE RECOGNITION - Additional Information (Details) - USD ($) $ in Thousands |  | 1 Months Ended | 11 Months Ended | 12 Months Ended | 18 Months Ended
--- | --- | --- | --- | --- | ---
Jun. 20, 2017 | May 31, 2020 | Jun. 05, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Jun. 30, 2020
Related Party Transaction [Line Items] |  |  |  |  |  |
Prepayments received |  |  |  |  | $ 11,050 |
Affiliated Entity | Shenghe |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Deferred revenue percentage recognized from gross profit | 64.00% |  |  |  |  |
Tariff rebates |  | $ 1,400 |  |  |  |
Affiliated Entity | Shenghe | Offtake Advances |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Reduction in principal debt balance due to tariff rebate |  |  |  | $ 2,000 | $ 9,300 |
Affiliated Entity | Shenghe | Shenghe Implied Discount |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Shenghe Implied Discount, percentage of contractual gross profit | 36.00% |  |  |  |  | 36.00%
Affiliated Entity | Shenghe | Minimum | Shenge Sales Discount |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Related parties, sales discount |  |  | 3.00% |  |  |
Affiliated Entity | Shenghe | Maximum | Shenge Sales Discount |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Related parties, sales discount |  |  | 6.00% |  |  |

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- Details
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