Separation Transaction and Discontinued Operations - Summary of Discontinued Operations in Statement of Consolidated Cash Flows (Detail) - Alcoa Corporation [Member] $ in Millions	6 Months Ended
Jun. 30, 2016 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Depreciation, depletion and amortization	$ 352
Restructuring and other charges	86
Capital expenditures	$ 172

Restructuring and other charges for discontinued operations.

No definition available.

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- Definition

Amount of capital expenditure attributable to discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

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- Definition

Amount of deprecation and amortization expense attributable to property, plant and equipment and intangible assets of discontinued operations.

+ References

+ Details

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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.

+ Details

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