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General (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Bargain purchase gain	$ 0.0	$ 245.9
Bauxite Mining and Alumina Refinery Joint Venture
Segment Reporting Information [Line Items]
Noncontrolling interest, ownership percentage by parent	55.00%
General Alumina Holdings Limited
Segment Reporting Information [Line Items]
Bargain purchase gain		$ 245.9

X

- Definition

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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-Name Accounting Standards Codification
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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

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- Definition

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.

+ References

No definition available.

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