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Acquisition of Jamalco - Narrative (Details) - USD ($) |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
May 02, 2023 | Sep. 30, 2023 | Sep. 30, 2023
General Alumina Holdings Limited |  |  |
Business Acquisition [Line Items] |  |  |
Total consideration transferred | $ 8,300,000 |  |
Other payments | 1.00 |  |
Cash paid | $ 8,300,000 |  |
Transaction costs |  | $ 200,000 | $ 1,900,000
Jamalco | General Alumina Holdings Limited |  |  |
Business Acquisition [Line Items] |  |  |
Noncontrolling interest, ownership percentage by parent | 55.00% |  |
Jamalco | Clarendon Alumina Production Limited |  |  |
Business Acquisition [Line Items] |  |  |
Ownership percentage by noncontrolling owners | 45.00% |  |

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