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Arconic Inc. Separation Transaction and Discontinued Operations - Summary of Property, Plant and Equipment Purchases of the Discontinued Operations (Details) - Arconic Corporation - Discontinued Operations, Disposed of by Means Other than Sale $ in Millions | 9 Months Ended
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Sep. 30, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |
Capital expenditures | $ 72
Proceeds from the sales of businesses | 112
Provision for depreciation and amortization | $ 58

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