Cash outlays.

No definition available.

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- Definition

Cash outlays expected over next three years.

+ References

No definition available.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes expenses related to certain asset retirement obligations.

+ References

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Paragraph 28
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-Name Accounting Standards Codification
-Topic 360
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-Section 45
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- Definition

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=116847112&loc=d3e4542-108314

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- Definition

The number of positions eliminated during the period as a result of restructuring activities.

+ References

No definition available.

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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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- Definition

Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph 210-10-S99-1(SX 210.5-02(24))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI https://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Topic 420
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-URI https://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

+ References

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Restructuring and Other Charges, Net - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2023 USD ($) Employees	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)	$ 149	$ 125
MRN [Member]
Restructuring Cost and Reserve [Line Items]
Asset impairments		58
Alcoa Corporation [Member]
Restructuring Cost and Reserve [Line Items]
Noncurrent portion of the reserve	44		$ 3
Intalco [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)	101
Asset impairments	50
Severance costs	$ 1
Number of employees associated with employee termination and severance costs \| Employees	12
Cash outlays expected over next three years	$ 85
Cash outlays spent in 2023	25
Cost of Goods Sold [Member] \| Intalco [Member]
Restructuring Cost and Reserve [Line Items]
Other costs	16
Restructuring and Other Charges [Member] \| San Ciprian Facility [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)	47
2023 Restructuring Plans Action [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)	149
Legal Disputes Related to 2019 Divestiture [Member] \| Aviles and La Coruna (Spain) Facilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)		77
Additional Contract Costs [Member] \| Wenatchee (Washington) and Intalco [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)		(9)
2022 Restructuring Plans Action [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)		$ 125
Closure Cost [Member] \| Intalco [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)	117
Asset impairments	101
Certain Employee Obligations [Member] \| San Ciprian Facility [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)	47
Environmental and Demolition Obligation [Member] \| Intalco [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)	50
Other Miscellaneous Charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges, net (D)	$ 1