v3.22.2.2

Recently Adopted and Recently Issued Accounting Guidance (Details) $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2022 USD ($)
Financing Receivable |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Financing Receivable, Capacity | $ 250

X
- Definition Financing Receivable, Capacity + References No definition available. + Details
Name: | arnc_FinancingReceivableCapacity
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=us-gaap_FinanceReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |