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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.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Arconic Inc Separation Transaction and Discontinued Operations - Narrative (Details)				3 Months Ended	6 Months Ended	12 Months Ended
	Apr. 01, 2020 company	Mar. 25, 2020 USD ($)	Feb. 01, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2021 USD ($)	Feb. 07, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of independent, publicly-traded companies resulting from proposed separation transaction \| company	2
Debt issuance costs (C and R)						$ 0	$ 11,000,000	$ 61,000,000
Asset impairment charges						$ 1,000,000	15,000,000	5,000,000
Aluminum Rolling Mill
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration			$ 50,000,000
Gain (loss) on disposition of business, before tax			$ (59,000,000)
Asset impairment charges				$ 6,000,000	$ 53,000,000			6,000,000
Hard Alloy Extrusions Plant In South Korea
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration							$ 62,000,000		$ 62,000,000
Lien Notes
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Debt issuance costs (C and R)				$ 45,000,000				$ 45,000,000
Senior Notes \| Second-Lien Notes Due 2028
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Aggregate principal amount										$ 600,000,000
Convertible notes, interest rate percentage										6.125%
Line of Credit \| Senior Secured First Lien Term B Loan Facility Due 2027 \| Secured Debt
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Aggregate principal amount		$ 600,000,000
Debt instrument, term		7 years