Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisition of Jamalco - Narrative (Details) - USD ($)		3 Months Ended
Acquisition of Jamalco - Narrative (Details) - USD ($)	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%