Arconic Inc. Separation Transaction and Discontinued Operations - Summary of Property, Plant and Equipment Purchases of the Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Provision for depreciation and amortization	$ 0	$ 61	$ 59	$ 122
Discontinued Operations, Disposed of by Means Other than Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Capital Expenditures	0	35	25	81
Proceeds from the sales of businesses	$ 0	$ 0	$ 112	$ 0

Amount of capital expenditure attributable to discontinued operations.

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-Publisher FASB
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-Topic 205
-SubTopic 20
-Section 50
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Amount of deprecation and amortization expense attributable to property, plant and equipment and intangible assets of discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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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.

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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.

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