Cash expense related to divestiture of businesses.

No definition available.

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- Definition

Guarantee payments to third party.

+ References

No definition available.

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- Definition

Number of employees.

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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

Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

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- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

+ Details

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- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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 - Narrative (Detail) $ in Millions		1 Months Ended	3 Months Ended
	Apr. 02, 2018 USD ($)	Mar. 31, 2017 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2017 USD ($) employee
Business Acquisition [Line Items]
Third-party sale generated in last annual period prior to divestiture			$ 3,445		$ 3,192
Restructuring and other charges			7		73
Latin America Extrusions (LAE) \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Business Acquisition [Line Items]
Disposal group, including discontinued operation, revenue			$ 25		26
Latin America Extrusions (LAE) \| Divested Businesses \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Business Acquisition [Line Items]
Restructuring and other charges				$ 41
Subsequent Event \| Latin America Extrusions (LAE) \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Business Acquisition [Line Items]
Cash received on sale of operations	$ 5
Slim Aluminium
Business Acquisition [Line Items]
Cash expense related to sale of rolling mill		$ 10
Third party guarantee with a fair value related to environmental remediation		$ 5
Disposal group, including discontinued operation, revenue					$ 37
Number of employees \| employee					312
Slim Aluminium \| Restructuring and Other Charges
Business Acquisition [Line Items]
Loss on sale of rolling mill					$ 60