Recently Adopted and Recently Issued Accounting Guidance	6 Months Ended
Jun. 30, 2022
Accounting Policies [Abstract]
Recently Adopted and Recently Issued Accounting Guidance	Recently Adopted and Recently Issued Accounting Guidance Issued In March 2020, the FASB issued guidance that provides optional expedients and exceptions for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. These expedients and exceptions may be used when applying GAAP, if certain criteria are met, to contracts, hedging relationships, and other transactions that reference London Inter-Bank Offered Rate (LIBOR) or another reference rate expected to be discontinued because of such reform. The purpose of this guidance is to provide relief to entities from experiencing unintended accounting and/or financial reporting outcomes or consequences due to reference rate reform. This guidance became effective immediately on March 12, 2020 and may be applied prospectively to contract modifications made and hedging relationships entered into or evaluated on or before December 31, 2022, after which time the expedients and exceptions expire. In January 2021, the FASB issued clarifying guidance to specify that certain of the optional expedients and exceptions apply to derivatives that use an interest rate for margining, discounting, or contract price alignment that is modified as a result of reference rate reform. This additional guidance may be applied on a full retrospective basis as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively in the manner previously described for the guidance issued on March 12, 2020. As of June 30, 2022, Arconic has not experienced any unintended outcomes or consequences of reference rate reform that would necessitate the adoption of this guidance. Additionally, the Company’s credit agreement, which previously provided a credit facility that was referenced to LIBOR in certain borrowing situations, was amended in February 2022 to replace LIBOR with the Secured Overnight Financing Rate (SOFR) (see Note N). Management will continue to closely monitor all potential instances of reference rate reform to determine if adoption of this guidance becomes necessary in the future.

In March 2020, the FASB issued guidance that provides optional expedients and exceptions for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. These expedients and exceptions may be used when applying GAAP, if certain criteria are met, to contracts, hedging relationships, and other transactions that reference London Inter-Bank Offered Rate (LIBOR) or another reference rate expected to be discontinued because of such reform. The purpose of this guidance is to provide relief to entities from experiencing unintended accounting and/or financial reporting outcomes or consequences due to reference rate reform. This guidance became effective immediately on March 12, 2020 and may be applied prospectively to contract modifications made and hedging relationships entered into or evaluated on or before December 31, 2022, after which time the expedients and exceptions expire. In January 2021, the FASB issued clarifying guidance to specify that certain of the optional expedients and exceptions apply to derivatives that use an interest rate for margining, discounting, or contract price alignment that is modified as a result of reference rate reform. This additional guidance may be applied on a full retrospective basis as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively in the manner previously described for the guidance issued on March 12, 2020. As of June 30, 2022, Arconic has not experienced any unintended outcomes or consequences of reference rate reform that would necessitate the adoption of this guidance. Additionally, the Company’s credit agreement, which previously provided a credit facility that was referenced to LIBOR in certain borrowing situations, was amended in February 2022 to replace LIBOR with the Secured Overnight Financing Rate (SOFR) (see Note N). Management will continue to closely monitor all potential instances of reference rate reform to determine if adoption of this guidance becomes necessary in the future.