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Related Party Expenses (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2026 | Mar. 31, 2025
Related Party Transaction [Line Items] |  |
General and administrative expenses | $ 114 | $ 112
Marathon Petroleum Corporation [Member] |  |
Related Party Transaction [Line Items] |  |
General and administrative expenses | 88 | 75
Asset under Construction [Member] | Marathon Petroleum Corporation [Member] |  |
Related Party Transaction [Line Items] |  |
Property, Plant and Equipment, Additions | $ 53 | $ 49

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- Definition Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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