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Acquisition of Jamalco - Narrative (Details) - USD ($) |  | 3 Months Ended
--- | --- | ---
May 02, 2023 | Mar. 31, 2024 | Mar. 31, 2023
Business Acquisition [Line Items] |  |  |
Bargain purchase gain |  | $ 245,900,000 | $ 0
General Alumina Holdings Limited |  |  |
Business Acquisition [Line Items] |  |  |
Payments to acquire business | $ 1.00 |  |
Bargain purchase gain |  | $ 245,900,000 |
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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