v3.22.4

Acquisitions and Divestitures (Details) |  |  |  | 1 Months Ended | 3 Months Ended | 10 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Nov. 15, 2022 USD ($) | Mar. 01, 2020 USD ($) employee | Feb. 01, 2020 USD ($) employee | Jun. 30, 2021 USD ($) | Dec. 31, 2020 USD ($) | May 31, 2020 USD ($) | Feb. 29, 2020 USD ($) | Oct. 31, 2018 USD ($) | Sep. 30, 2021 USD ($) | Nov. 14, 2022 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash payments to settle working capital and other adjustments |  |  |  | $ 2,000,000 |  |  |  |  |  |  |  |  |  |
Goodwill, Impairment Loss |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 65,000,000 | $ 0 |
Total sales |  |  |  |  |  |  |  |  |  |  | 8,961,000,000 | 7,504,000,000 | 5,675,000,000 |
Goodwill, Written off Related to Sale of Business Unit |  |  |  |  |  |  |  |  |  |  | 14,000,000 |  |  |
Segment total |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total sales |  |  |  |  |  |  |  |  |  |  | 9,013,000,000 | 7,538,000,000 | 5,700,000,000 |
Segment Adjusted EBITDA |  |  |  |  |  |  |  |  |  |  | 729,000,000 | 757,000,000 | 648,000,000 |
Rolled Products |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Goodwill, Impairment Loss |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  |
Goodwill, Written off Related to Sale of Business Unit |  |  |  |  |  |  |  |  |  |  | 14,000,000 |  |  |
Rolled Products | Segment total |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total sales |  |  |  |  |  |  |  |  |  |  | 7,357,000,000 | 6,220,000,000 | 4,354,000,000 |
Segment Adjusted EBITDA |  |  |  |  |  |  |  |  |  |  | 581,000,000 | 655,000,000 | 527,000,000 |
Kawneer Brand |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total sales |  |  |  |  |  |  |  |  |  |  | $ 970,000,000 |  |  |
Number of employees |  |  |  |  |  |  |  |  |  |  | 2,900 |  |  |
Disposed of by sale | Samara Manufacturing Site |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consideration received | $ 230,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Goodwill, Impairment Loss |  |  |  |  |  |  |  |  |  |  | $ 14,000,000 |  |  |
Number of employees |  |  |  |  |  |  |  |  |  | 2,900 |  |  |  |
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents |  |  |  |  |  |  |  |  |  | $ 203,000,000 |  | 79,000,000 |  |
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net |  |  |  |  |  |  |  |  |  | 100,000,000 |  | 120,000,000 |  |
Disposal Group, Including Discontinued Operation, Inventory, Current |  |  |  |  |  |  |  |  |  | 129,000,000 |  | 102,000,000 |  |
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Noncurrent |  |  |  |  |  |  |  |  |  | 184,000,000 |  | 200,000,000 |  |
Disposal Group, Not Discontinued Operation, After tax Gain (Loss) on Disposal | $ (304,000,000) |  |  |  |  |  |  |  |  |  |  |  |  |
Disposal Group, Including Discontinued Operation, Accounts Payable, Current |  |  |  |  |  |  |  |  |  | 55,000,000 |  | 47,000,000 |  |
Disposal Group, Including Discontinued Operation, Revenue |  |  |  |  |  |  |  |  |  | 903,000,000 |  | 968,000,000 |  |
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal, Statement of Income or Comprehensive Income [Extensible Enumeration] | Restructuring and other charges |  |  |  |  |  |  |  |  |  |  |  |  |
Disposed of by sale | Samara Manufacturing Site | Rolled Products | Segment total |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Adjusted EBITDA |  |  |  |  |  |  |  |  |  | $ 71,000,000 |  | 87,000,000 |  |
Disposed of by sale | Aluminum Rolling Mill in Itapissuma, Brazil |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consideration received |  |  | $ 46,000,000 |  |  |  |  |  |  |  |  |  |  |
Gain (loss) on sale |  |  | $ (60,000,000) |  |  |  |  |  |  |  |  |  |  |
Charges (credits) associated with sale |  |  |  |  |  |  | $ 6,000,000 |  |  |  |  | $ 53,000,000 |  |
Cash payments to settle working capital and other adjustments |  |  |  |  | $ 4,000,000 |  |  |  |  |  |  |  |  |
Additional cash received as a post-closing adjustment |  |  |  |  |  |  |  |  | $ 1,000,000 |  |  |  |  |
Total sales |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 143,000,000
Number of employees | employee |  |  | 500 |  |  |  |  |  |  |  |  |  |  |
Disposed of by sale | Hard Alloy Extrusions Plant in South Korea |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consideration received |  | $ 55,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Gain (loss) on sale |  | 31,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Goodwill, Impairment Loss |  | $ 6,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Additional cash received as a post-closing adjustment |  |  |  |  |  | $ 1,000,000 |  |  |  |  |  |  |  |
Total sales |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 51,000,000
Number of employees | employee |  | 160 |  |  |  |  |  |  |  |  |  |  |  |
Disposed of by sale | Texarkana Rolling Mill and Cast House |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Consideration received |  |  |  |  |  |  |  | $ 302,000,000 |  |  |  |  |  |
Net book value |  |  |  |  |  |  |  | 63,000,000 |  |  |  |  |  |
Additional contingent consideration (up to) |  |  |  |  | $ 25,000,000 |  |  | $ 50,000,000 |  |  |  |  | $ 25,000,000 |
Period post transaction closing date for measurement of various milestones required to achieve for additional contingent consideration |  |  |  |  |  |  |  | 36 months |  |  |  |  |  |

X
- Definition Disposal Group, Including Discontinued Operation, Assets (Liabilities), Net + References No definition available. + Details
Name: | arnc_DisposalGroupIncludingDiscontinuedOperationAssetsLiabilitiesNet
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Disposal Group, Including Discontinued Operation, Consideration, Additional Consideration, Period Post Transaction Closing Date + References No definition available. + Details
Name: | arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationAdditionalConsiderationPeriodPostTransactionClosingDate
Namespace Prefix: | arnc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Disposal Group, Including Discontinued Operations, Consideration, Additional Contingent Consideration + References No definition available. + Details
Name: | arnc_DisposalGroupIncludingDiscontinuedOperationsConsiderationAdditionalContingentConsideration
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Disposal Group, Not Discontinued Operation, After tax Gain (Loss) on Disposal + References No definition available. + Details
Name: | arnc_DisposalGroupNotDiscontinuedOperationAfterTaxGainLossOnDisposal
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Income (Loss) Before Interest, Taxes, Depreciation and Amortization, Adjusted + References No definition available. + Details
Name: | arnc_IncomeLossBeforeInterestTaxesDepreciationAndAmortizationAdjusted
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of Employees + References No definition available. + Details
Name: | arnc_NumberofEmployees
Namespace Prefix: | arnc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Payments To Settle Working Capital And Other Adjustments Related To Disposal + References No definition available. + Details
Name: | arnc_PaymentsToSettleWorkingCapitalAndOtherAdjustmentsRelatedToDisposal
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=109222160&loc=d3e1107-107759 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759 + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount classified as accounts payable attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 9 -URI https://asc.fasb.org/extlink&oid=126905981&loc=d3e2473-110228 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=109222160&loc=d3e1107-107759 + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount classified as cash and cash equivalents attributable to disposal group held for sale or disposed of. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=109222160&loc=d3e1107-107759 + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation. + References No definition available. + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount classified as inventory attributable to disposal group, expected to be disposed of within one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 9 -URI https://asc.fasb.org/extlink&oid=126905981&loc=d3e2473-110228 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=109222160&loc=d3e1107-107759 + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=109222160&loc=d3e1107-107759 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=126905981&loc=d3e2510-110228 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 7 -URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760 + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126905981&loc=d3e2443-110228 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 + Details
Name: | us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Indicates line item in statement of income that includes gain (loss) recognized on sale or disposal of disposal group. Excludes discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 + Details
Name: | us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposalStatementOfIncomeExtensibleList
Namespace Prefix: | us-gaap_
Data Type: | enum2:enumerationSetItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, before tax, of (gain) loss recognized for the (reversal of write-down) write-down to fair value, less cost to sell, of a disposal group. Excludes discontinued operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126905981&loc=d3e2443-110228 + Details
Name: | us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13854-109267 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 55 -Paragraph 24 -URI https://asc.fasb.org/extlink&oid=122137925&loc=d3e14258-109268 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267 + Details
Name: | us-gaap_GoodwillImpairmentLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 55 -Paragraph 24 -URI https://asc.fasb.org/extlink&oid=122137925&loc=d3e14258-109268 + Details
Name: | us-gaap_GoodwillWrittenOffRelatedToSaleOfBusinessUnit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3179-108585 + Details
Name: | us-gaap_ProceedsFromDivestitureOfBusinesses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 40 -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9031-108599 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 41 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9038-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130543-203045 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 42 -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9054-108599 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130545-203045 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 924 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 11.L) -URI https://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856 + Details
Name: | us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=arnc_RolledProductsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=arnc_KawneerBrandMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DisposalGroupClassificationAxis=us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=arnc_SamaraManufacturingSiteMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=arnc_AluminumRollingMillinItapissumaBrazilMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=arnc_HardAlloyExtrusionsPlantinSouthKoreaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=arnc_TexarkanaRollingMillAndCastHouseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |