XML 105 R85.htm IDEA: XBRL DOCUMENT
v3.25.0.1

Income Taxes - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Income Tax Contingency [Line Items] |  |  |  |
Temporary differences that reverses (as a percent) | 5.00% |  |  |
Temporary differences that reverses within the carryforward period (as a percent) | 95.00% |  |  |
Foreign tax credits | $ 46 | $ 20 |  |
Increase (decrease) to valuation allowance | 20 | 21 | $ 40 |
Cumulative amount of valuation allowance | 41 |  |  |
Valuation allowance | 1,705 | 1,821 | 1,965 | $ 2,279
Income taxes, net of amounts refunded | $ 177 | $ 104 | $ 50 |
Percentage of the effect of unrecognized tax benefit, if recorded (less than) | 1.00% | 2.00% | 1.00% |
Interest or penalties recognized (less than for 2022) | $ 1 | $ 7 | $ 1 |
Income related to accrued interest and penalties (less than for 2022) | 0 | 2 | 1 |
Amount accrued for payment of interest and penalties (less than for 2022) | 9 | 11 | 1 |
State and Local |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Increase (decrease) to valuation allowance | (7) | (2) | (1) |
Foreign | UK Tax Authority |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Increase (decrease) to valuation allowance |  |  | (6) |
Foreign Tax Credit Carryover |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Increase (decrease) to valuation allowance | (4) | (14) |  |
Other Net State Deferred Tax Asset | State and Local |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Increase (decrease) to valuation allowance | (30) | $ (49) | $ (142) |
Valuation allowance | $ 401 |  |  |

X
- Definition Deferred Tax Assets, Tax Credit Carryforwards, Foreign, Expired During Period + References No definition available. + Details
Name: | hwm_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod
Namespace Prefix: | hwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Deferred Tax Assets, Valuation Allowance, Foreign Tax Credit + References No definition available. + Details
Name: | hwm_DeferredTaxAssetsValuationAllowanceForeignTaxCredit
Namespace Prefix: | hwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Interest Income From Income Taxes + References No definition available. + Details
Name: | hwm_InterestIncomeFromIncomeTaxes
Namespace Prefix: | hwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Percentage of the effect of unrecognized tax benefit, if recorded. + References No definition available. + Details
Name: | hwm_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded
Namespace Prefix: | hwm_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Taxable Temporary Differences, Subject To Reversal Within The Carryforward Period + References No definition available. + Details
Name: | hwm_TaxableTemporaryDifferencesSubjectToReversalWithinTheCarryforwardPeriod
Namespace Prefix: | hwm_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Taxable Temporary Differences Subject To Reversals + References No definition available. + Details
Name: | hwm_TaxableTemporaryDifferencesSubjectToReversals
Namespace Prefix: | hwm_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-2 + Details
Name: | us-gaap_DeferredTaxAssetsValuationAllowance
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_IncomeTaxContingencyLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482913/230-10-50-2A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 23 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-23 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-22 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482913/230-10-50-2 + Details
Name: | us-gaap_IncomeTaxesPaidNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 217 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-217 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 15 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-15 + Details
Name: | us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 217 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-217 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 15 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-15 + Details
Name: | us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-2 + Details
Name: | us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_StateAndLocalJurisdictionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_ForeignCountryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityNameAxis=us-gaap_HerMajestysRevenueAndCustomsHMRCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationAllowanceByDeferredTaxAssetAxis=hwm_ForeignTaxCreditCarryoverMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationAllowanceByDeferredTaxAssetAxis=hwm_OtherNetStateDeferredTaxAssetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |