XML 66 R57.htm IDEA: XBRL DOCUMENT
v3.20.2

Income Taxes - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Error Corrections and Prior Period Adjustments Restatement [Line Items] |  |  |  |  |  |
Effective income tax rate reconciliation (percent) | 36.10% | 51.80% | 36.10% | 51.80% |  |
Effective income tax rate reconciliation, including discrete items (percent) | (2.30%) | (49.30%) | 2.30% | (49.30%) |  |
Discrete income tax charge (benefit) | $ 10 | $ (37) |  | $ (37) |  |
Income tax charge related to remeasurement as a result of the Separation Transaction | 6 |  |  |  |  |
Income tax charge for prior year items | 4 |  |  |  |  |
Income tax benefit from deduction of prior year foreign taxes |  | (25) |  | 25 |  |
Income tax benefit from remeasurement of certain deferred tax assets |  | $ 12 |  | $ 12 |  |
Tax misstatement recorded to retained earnings | $ 223 |  | $ 223 |  | $ 129 |
Revision of Prior Period, Error Correction, Adjustment |  |  |  |  |  |
Error Corrections and Prior Period Adjustments Restatement [Line Items] |  |  |  |  |  |
Tax misstatement recorded to retained earnings |  |  |  |  |  | $ 16

X
- Definition Discrete Income Tax Expense (Benefit) + References No definition available. + Details
Name: | arnc_DiscreteIncomeTaxExpenseBenefit
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Effective Income Tax Rate Reconciliation, Deduction, Foreign Taxes, Amount + References No definition available. + Details
Name: | arnc_EffectiveIncomeTaxRateReconciliationDeductionForeignTaxesAmount
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Effective Income Tax Rate Reconciliation, Including Discrete Items, Percent + References No definition available. + Details
Name: | arnc_EffectiveIncomeTaxRateReconciliationIncludingDiscreteItemsPercent
Namespace Prefix: | arnc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Effective Income Tax Rate Reconciliation, Remeasurement Due To Separation Agreement, Amount + References No definition available. + Details
Name: | arnc_EffectiveIncomeTaxRateReconciliationRemeasurementDueToSeparationAgreementAmount
Namespace Prefix: | arnc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
Name: | us-gaap_EffectiveIncomeTaxRateContinuingOperations
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
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_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e32059-109318 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to revisions of previously reported income tax expense (benefit). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationPriorYearIncomeTaxes
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(30)(a)(3)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (g)(2) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(a)(4)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(i) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 + Details
Name: | us-gaap_RetainedEarningsAccumulatedDeficit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | srt_RestatementAxis=srt_RevisionOfPriorPeriodErrorCorrectionAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |