Number of operating smelting potlines.

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- Definition

Number of operating smelting potlines curtailed.

+ References

No definition available.

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- Definition

Number of product divisions.

+ References

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- Definition

Operating smelting potlines aluminium facility in Kilo Metric Ton.

+ References

No definition available.

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- Definition

Ownership interest in joint venture.

+ References

No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8672-108599

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ 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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Segment and Related Information - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023 Segment	Dec. 31, 2022 Segment Product_Division	Jul. 01, 2022 Kmt Potline
Segment Reporting Information [Line Items]
Number of operating segments		3
Number of reportable segments		3
Number of operating smelting potlines curtailed \| Potline			1
Number of operating smelting potlines \| Potline			3
Operating smelting potlines aluminium facility in Kilo Metric Ton \| Kmt			54
Number of product divisions \| Product_Division		4
Alcoa Corporation [Member]
Segment Reporting Information [Line Items]
Ownership interest in joint venture		25.10%
AWAC [Member]
Segment Reporting Information [Line Items]
Ownership interest in joint venture		25.10%
Scenario Forecast [Member]
Segment Reporting Information [Line Items]
Number of operating segments	2