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Commitments and Contingencies (Detail) - USD ($) $ in Millions |  | 1 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 15, 2020 | Jul. 31, 2020 | Dec. 31, 2025 | Dec. 31, 2024
Commitments And Contingencies [Line Items] |  |  |  |
Accrual for environmental loss contingencies |  |  | $ 21 | $ 15
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration] |  |  | Other Liabilities, Current, Other Long-term Liabilities | Other Liabilities, Current, Other Long-term Liabilities
Loss Contingency, Damages Sought, Value |  | $ 187 |  |
Loss Contingency, Damages Paid, Value | $ 4 |  |  |
Capital Addition Purchase Commitments |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Contractual commitments to acquire property, plant and equipment |  |  | $ 311 |
Indirect Ownership Interest | Bakken Pipeline System | Crude Oil and Products Logistics [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Equity Method Investment, Ownership Percentage |  |  | 9.19% |
Financial Guarantee | Bakken Pipeline System | Guarantee of Indebtedness of Others |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Guarantor Obligations, Maximum Exposure, Undiscounted |  |  | $ 78 |
Performance Guarantee | WPC Parent, LLC |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Guarantor Obligations, Maximum Exposure, Undiscounted |  |  | $ 109 |

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