Business acquisition debt position exceeds.

No definition available.

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- Definition

Business disposition.

+ References

No definition available.

+ Details

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- Definition

Estimated liabilities for future site separation commitment charge.

+ References

No definition available.

+ Details

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- Definition

Liabilities recorded from disposal group including discontinued operation.

+ References

No definition available.

+ Details

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- Definition

Payments for financial contributions for divestiture of businesses.

+ References

No definition available.

+ Details

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479581/805-30-50-1

+ Details

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

+ Details

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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- Details

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- Details

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- Details

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- Details

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- Details

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Acquisitions and Divestitures - Additional Information (Detail) $ in Millions		3 Months Ended
	Mar. 11, 2024 USD ($) shares	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Feb. 23, 2024 $ / shares	Feb. 23, 2024 USD ($)
Warrick Rolling Mill [Member] \| Disposal Group, Held-for-Sale, Not Discontinued Operations [Member]
Business Disposition [Line Items]
Estimated liabilities for future site separation commitment charge		$ 11	$ 17
Payments against the reserve		7	$ 14
Remaining reserve		$ 15
Alumina Limited [Member] \| Minimum [Member]
Business Disposition [Line Items]
Debt position exceeds	$ 420
AWAC [Member] \| Alumina Limited [Member]
Business Disposition [Line Items]
Non-controlling interest, ownership percentage		40.00%
AWAC [Member] \| Alcoa Corporation [Member]
Business Disposition [Line Items]
Ownership interest percentage		60.00%
Scheme Implementation Deed [Member] \| Alumina Limited [Member]
Business Disposition [Line Items]
Business acquisition, shares issued for consideration \| shares	0.02854
Agreed ratio value per share \| $ / shares				$ 1.15
Equity value of share					$ 2,200
Scheme Implementation Deed [Member] \| AWAC [Member] \| Alcoa Corporation [Member]
Business Disposition [Line Items]
Ownership interest percentage	68.75%
Scheme Implementation Deed [Member] \| AWAC [Member] \| Alcoa Corporation [Member] \| Alumina Limited [Member]
Business Disposition [Line Items]
Non-controlling interest, ownership percentage	31.25%