Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions |
Dec. 31, 2025 |
Sep. 30, 2025 |
Dec. 31, 2024 |
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| Deferred Tax Liabilities | |||
| Properties, plants and equipment, and intangibles | $ 3,743 | $ 3,493 | |
| Investment in joint ventures | 1,094 | 1,864 | |
| Investment in subsidiaries | 3,188 | 2,511 | |
| Other | 342 | 318 | |
| Total deferred tax liabilities | 8,367 | 8,186 | |
| Deferred Tax Assets | |||
| Benefit plan accruals | 296 | 355 | |
| Loss and credit carryforwards | 209 | 162 | |
| Asset retirement obligations and accrued environmental costs | 422 | 299 | |
| Other financial accruals and deferrals | 72 | 91 | |
| Inventory | 8 | 82 | |
| Other | 246 | 299 | |
| Total deferred tax assets | 1,253 | 1,288 | |
| Less: valuation allowance | 160 | 137 | |
| Net deferred tax assets | 1,093 | 1,151 | |
| Net deferred tax liabilities | $ 7,274 | $ 7,035 | |
| WRB Refining LP | |||
| Deferred Tax Assets | |||
| Equity investment (as a percent) | 100.00% | 50.00% | 50.00% |
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- Definition Deferred Tax Assets, Operating Loss, Capital Loss And Foreign Tax Credit Carryforwards No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from asset retirement obligations and accrued environmental loss contingencies. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset and an accrued environmental loss contingency is an obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites. No definition available.
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- Definition Deferred Tax Liabilities, Investment in Subsidiaries No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment and intangible assets. No definition available.
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- References No definition available.
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- References No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from reserves and accruals, classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from investments in unconsolidated subsidiaries and investments in other affiliates which are not controlled nor consolidated. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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