Subsequent Events	12 Months Ended
Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Management evaluated all activity of Arconic and concluded that no subsequent events have occurred that would require recognition in the Consolidated Financial Statements or disclosure in the Notes to the Consolidated Financial Statements, except as described below. On January 5, 2022, Arconic entered into a one-year arrangement with a financial institution to sell certain customer receivables outright without recourse on a continuous basis. Under this arrangement, the Company will serve in an administrative capacity, including collection of the receivables from the respective customers and remittance of these cash collections to the financial institution. At no time can the outstanding balance due to the financial institution exceed $100. In January 2022, Arconic sold $113 in customer receivables, of which $77 were included in Receivables from customers on the accompanying Consolidated Balance Sheet as of December 31, 2021, and remitted $28 in cash collections to the financial institution. On February 16, 2022, the Company’s ABL Credit Agreement was amended to increase the capacity of the ABL Credit Facility to $1,200 from $800 (see Note Q). Additionally, the accordion feature of the ABL Credit Facility has been revised to provide for the Company to request a further increase to the revolving commitments in an aggregate principal amount equal to the greater of $350 and the excess of the borrowing base over the ABL Credit facility commitments. Arconic paid approximately $1 in upfront costs associated with this amendment. The ABL Credit Facility remains undrawn at February 18, 2022.

Management evaluated all activity of Arconic and concluded that no subsequent events have occurred that would require recognition in the Consolidated Financial Statements or disclosure in the Notes to the Consolidated Financial Statements, except as described below.

On January 5, 2022, Arconic entered into a one-year arrangement with a financial institution to sell certain customer receivables outright without recourse on a continuous basis. Under this arrangement, the Company will serve in an administrative capacity, including collection of the receivables from the respective customers and remittance of these cash collections to the financial institution. At no time can the outstanding balance due to the financial institution exceed $100. In January 2022, Arconic sold $113 in customer receivables, of which $77 were included in Receivables from customers on the accompanying Consolidated Balance Sheet as of December 31, 2021, and remitted $28 in cash collections to the financial institution.

On February 16, 2022, the Company’s ABL Credit Agreement was amended to increase the capacity of the ABL Credit Facility to $1,200 from $800 (see Note Q). Additionally, the accordion feature of the ABL Credit Facility has been revised to provide for the Company to request a further increase to the revolving commitments in an aggregate principal amount equal to the greater of $350 and the excess of the borrowing base over the ABL Credit facility commitments. Arconic paid approximately $1 in upfront costs associated with this amendment. The ABL Credit Facility remains undrawn at February 18, 2022.