XML 62 R52.htm IDEA: XBRL DOCUMENT
v3.23.1

Income Taxes - Narrative (Details) € in Millions, $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2023 USD ($) | Mar. 31, 2023 EUR (€) | Mar. 31, 2022 USD ($)
Income Tax Disclosure [Abstract] |  |  |
Effective income tax rate reconciliation (percent) | 23.40% | 23.40% | 24.30%
Effective income tax rate reconciliation, including discrete items (percent) | 32.70% | 32.70% | 23.40%
Income tax reserve | $ 20 | € 19 | $ 0
Other discrete items, tax charge (benefit) | $ 1 |  | $ (2)

X
- Definition Effective Income Tax Rate Reconciliation, Including Discrete Items, Percent + References No definition available. + Details
Name: | hwm_EffectiveIncomeTaxRateReconciliationIncludingDiscreteItemsPercent
Namespace Prefix: | hwm_
Data Type: | dtr-types:percentItemType
Balance Type: | na
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 https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
Name: | us-gaap_EffectiveIncomeTaxRateContinuingOperations
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_IncomeTaxDisclosureAbstract
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 tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments. + 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 https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationOtherReconcilingItems
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 increase (decrease) in income tax contingencies. Including, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies. + 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 https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationTaxContingencies
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration