v3.26.1
Related Party Expenses (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Related Party Transaction [Line Items]        
General and administrative expenses $ 108 $ 107 $ 222 $ 219
Marathon Petroleum Corporation [Member]        
Related Party Transaction [Line Items]        
General and administrative expenses 82 81 170 156
Asset under Construction [Member] | Marathon Petroleum Corporation [Member]        
Related Party Transaction [Line Items]        
Property, Plant, and Equipment, before Accumulated Depreciation, Addition $ 64 $ 46 $ 117 $ 95