XML 141 R125.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Contingencies and Commitments - Commitments (Details) $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2019 USD ($) agreement | Oct. 31, 2017 agreement | Dec. 31, 2017 USD ($) | Dec. 31, 2019 USD ($) agreement | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Sep. 30, 2018 agreement | Nov. 01, 2016 USD ($)
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Purchase obligations due in 2020 | $ 604 |  |  | $ 604 |  |  |  |
Purchase obligations due in 2021 | 93 |  |  | 93 |  |  |  |
Purchase obligations due in 2022 | 45 |  |  | 45 |  |  |  |
Purchase obligations due in 2023 | 12 |  |  | 12 |  |  |  |
Purchase obligations due in 2024 | 4 |  |  | 4 |  |  |  |
Purchase obligations due thereafter | 2 |  |  | 2 |  |  |  |
Guarantees of third party related to project financing | $ 31 |  |  | $ 31 |  |  |  |
Number of long term energy supply agreements | agreement | 2 |  |  | 2 |  |  | 2 |
Number of agreements terminated | agreement |  | 1 |  |  |  |  |  |
Other (expense) income, net |  |  |  | $ (122) | $ (79) | $ 486 |  |
Insurance policy coverage limit | $ 80 |  |  |  |  |  |  |
Insurance policy term | 1 year |  |  |  |  |  |  |
Total amount committed under outstanding surety bonds | $ 50 |  |  | 50 |  |  |  |
Amount of outstanding surety bonds relating to these liabilities | 24 |  |  | 24 |  |  |  |
Alcoa Corporation Workers Compensation Claims |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Letters of credit, total amount committed |  |  |  |  |  |  |  | $ 52
Separation Agreement |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Combined fair value of guarantees | 9 |  |  | 9 | 6 |  |  |
Other (expense) income, net |  |  | $ 25 |  |  |  |  |
Total amount committed under outstanding surety bonds |  |  | $ 25 |  |  | $ 25 |  |
Separation Agreement | Other Noncurrent Liabilities and Deferred Credits |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Guarantees of third party related to project financing | 1,353 |  |  | 1,353 | $ 1,087 |  |  |
Bank Loan Obligations |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Letters of credit | $ 142 |  |  | $ 142 |  |  |  |

X
- Definition Amount Committed Under Outstanding Surety Bonds + References No definition available. + Details
Name: | arnc_AmountCommittedUnderOutstandingSuretyBonds
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Insurance, Annual Coverage Limit + References No definition available. + Details
Name: | arnc_InsuranceAnnualCoverageLimit
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Insurance, Policy Term + References No definition available. + Details
Name: | arnc_InsurancePolicyTerm
Namespace Prefix: | arnc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Letters Of Credit, Total + References No definition available. + Details
Name: | arnc_LettersOfCreditTotal
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number Of Long Term Energy Supply Agreements + References No definition available. + Details
Name: | arnc_NumberOfLongTermEnergySupplyAgreements
Namespace Prefix: | arnc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of Agreements Terminated + References No definition available. + Details
Name: | arnc_NumberofAgreementsTerminated
Namespace Prefix: | arnc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Separation And Distribution Agreement, Surety Bonds, Amount Outstanding + References No definition available. + Details
Name: | arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248 + Details
Name: | us-gaap_GuaranteeObligationsCurrentCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248 + Details
Name: | us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12201-110248 + Details
Name: | us-gaap_GuaranteesFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
Name: | us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
Name: | us-gaap_NonoperatingIncomeExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of the recorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25383-109308 + Details
Name: | us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of the recorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25383-109308 + Details
Name: | us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of the recorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25383-109308 + Details
Name: | us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of the recorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25383-109308 + Details
Name: | us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of the recorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25383-109308 + Details
Name: | us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of the recorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25383-109308 + Details
Name: | us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=arnc_AlcoaCorporationWorkersCompensationClaimsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=arnc_SeparationAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_BankLoanObligationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |