| Component: (Network and Table) | |
|---|---|
| Network | 2414407 - Disclosure - Income Taxes (Summary Of Income Tax Returns Subject To Examination) (Detail) (http://www.marathonpetroleum.com/role/IncomeTaxesSummaryOfIncomeTaxReturnsSubjectToExaminationDetail) |
| Table | Income Tax Examination [Table] |
| Reporting Entity [Axis] | 0001510295 (http://www.sec.gov/CIK) |
| Period [Axis] | 2012-01-01 - 2012-12-31 |
| Income Tax Examination [Line Items] | Range [Axis] | |||
|---|---|---|---|---|
| Minimum [Member] | Maximum [Member] | |||
| Income Tax Authority [Axis] | Income Tax Authority [Axis] | |||
| Domestic Tax Authority [Member] | State and Local Jurisdiction [Member] | Domestic Tax Authority [Member] | State and Local Jurisdiction [Member] | |
Tax years | ||||