| Pay vs Performance Disclosure | 4 Months Ended | 12 Months Ended |
| Apr. 29, 2020 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) |
| Pay vs Performance Disclosure | | | | | |
| Pay vs Performance Disclosure, Table | | Pay Versus Performance SEC rules require us to disclose the following information concerning executive compensation and certain financial performance information about the Company for the periods shown. Based on 2023 SEC guidance, some amounts shown in the following tables have been calculated differently than for the corresponding disclosure in our 2023 Proxy Statement. PAY VERSUS PERFORMANCE TABLE Year Summary Compensation Table Total for PEO ($) Compensation Actually Paid to PEO ($) Average Summary Compensation Table Total for Non-PEO NEOs ($) Average Compensation Actually Paid to Non-PEO NEOs ($) Value of Initial Fixed $100 Investment Based On: Net Income ($ millions) MPC Relative TSR Performance Percentile Total Shareholder Return ($) Peer Group Total Shareholder Return ($) 2023 24,054,492 49,644,470 5,557,272 10,633,993 284.79 189.79 11,172 100.00th 2022 21,288,532 54,026,557 4,759,899 11,070,030 218.21 153.61 16,050 83.33rd 2021 21,185,206 34,913,307 5,601,203 6,430,233 116.95 90.02 11,001 91.67th 2020 15,534,265 21,219,014 5,628,257 5,101,562 72.64 66.82 (9,977) 90.00th 10,005,700 10,070,251 | | | |
| Company Selected Measure Name | | MPC Relative TSR Performance Percentile | | | |
| Named Executive Officers, Footnote | | • 2023: Maryann T. Mannen, Timothy J. Aydt, Suzanne Gagle and Gregory S. Floerke • 2022: Ms. Mannen, Ms. Gagle, Mr. Aydt, Mr. Floerke and Raymond L. Brooks • 2021: Ms. Mannen, Mr. Brooks, Ms. Gagle, Brian C. Davis, Donald C. Templin and Timothy T. Griffith • 2020: Mr. Templin, Mr. Griffith, Mr. Brooks and Ms. Gagle | | | |
| Peer Group Issuers, Footnote | | Peer Group Total Shareholder Return is shown for the S&P 500 Oil & Gas Refining & Marketing Sub-Industry Index, the same peer group used for the Stock Return Performance Graph included in our 2023 Annual Report. | | | |
| PEO Total Compensation Amount | $ 10,005,700 | $ 24,054,492 | $ 21,288,532 | $ 21,185,206 | $ 15,534,265 |
| PEO Actually Paid Compensation Amount | 10,070,251 | $ 49,644,470 | 54,026,557 | 34,913,307 | 21,219,014 |
| Adjustment To PEO Compensation, Footnote | | PEO SCT TOTAL TO CAP TOTAL RECONCILIATION Deductions from SCT Total Additions to SCT Total Year SCT Total ($) Grant Date Fair Value of Equity-Based Awards ($) Change in Pension Value ($) Pension Service Cost ($) Change in Value of Equity Awards as Summarized Below ($) CAP Total ($) 2023 24,054,492 16,200,864 741,763 403,201 42,129,404 49,644,470 2022 21,288,532 13,925,769 595,747 374,531 46,885,010 54,026,557 2021 21,185,206 14,186,189 450,102 292,772 28,071,620 34,913,307 2020 * 15,534,265 10,092,339 440,104 234,235 15,982,957 21,219,014 10,005,700 6,000,009 — — 6,064,560 10,070,251 * Includes Mr. Hennigan (top row) and Mr. Heminger (bottom row). | | | |
| Non-PEO NEO Average Total Compensation Amount | | $ 5,557,272 | 4,759,899 | 5,601,203 | 5,628,257 |
| Non-PEO NEO Average Compensation Actually Paid Amount | | $ 10,633,993 | 11,070,030 | 6,430,233 | 5,101,562 |
| Adjustment to Non-PEO NEO Compensation Footnote | | NON-PEO NEO (AVERAGE) SCT TOTAL TO CAP TOTAL RECONCILIATION Deductions from SCT Total Additions to SCT Total Year SCT Total ($) Grant Date Fair Value of Equity-Based Awards ($) Change in Pension Value ($) Pension Service Cost ($) Change in Value of Equity Awards as Summarized Below ($) CAP Total ($) 2023 5,557,272 3,203,916 192,840 104,741 8,368,736 10,633,993 2022 4,759,899 2,807,979 82,922 94,246 9,106,786 11,070,030 2021 5,601,203 4,029,882 100,517 99,299 4,860,130 6,430,233 2020 5,628,257 2,815,663 493,663 164,855 2,617,776 5,101,562 | | | |
| Compensation Actually Paid vs. Total Shareholder Return | | | | | |
| Compensation Actually Paid vs. Net Income | | | | | |
| Compensation Actually Paid vs. Company Selected Measure | | | | | |
| Total Shareholder Return Vs Peer Group | | | | | |
| Tabular List, Table | | FINANCIAL PERFORMANCE MEASURES USED TO LINK NEO CAP TO MPC PERFORMANCE MPC Relative TSR Performance Percentile Relative Adjusted EBITDA per Barrel ACB Adjusted EBITDA Distributable Cash Flow at MPLX per Unit Refining and Corporate Costs | | | |
| Total Shareholder Return Amount | | $ 284.79 | 218.21 | 116.95 | 72.64 |
| Peer Group Total Shareholder Return Amount | | 189.79 | 153.61 | 90.02 | 66.82 |
| Net Income (Loss) | | $ 11,172,000,000 | $ 16,050,000,000 | $ 11,001,000,000 | $ (9,977,000,000) |
| Company Selected Measure Amount | | 100 | 83.33 | 91.67 | 90 |
| PEO Name | | •2023, 2022 and 2021: Michael J. Hennigan•2020: Mr. Hennigan (top row), who was promoted to the CEO role effective March 17, 2020, and Gary R. Heminger (bottom row), who stepped down from the CEO role on that date but continued to serve in his role as Chairman of the Board through April 29, 2020 | | | |
| Measure:: 1 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | | MPC Relative TSR Performance Percentile | | | |
| Measure:: 2 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | | Relative Adjusted EBITDA per Barrel | | | |
| Measure:: 3 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | | ACB Adjusted EBITDA | | | |
| Measure:: 4 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | | Distributable Cash Flow at MPLX per Unit | | | |
| Measure:: 5 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | | Refining and Corporate Costs | | | |
| PEO | Grant Date Fair Value of Equity-Based Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (6,000,009) | $ (16,200,864) | $ (13,925,769) | $ (14,186,189) | $ (10,092,339) |
| PEO | Change in Pension Value [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 0 | (741,763) | (595,747) | (450,102) | (440,104) |
| PEO | Pension Service Cost [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 0 | 403,201 | 374,531 | 292,772 | 234,235 |
| PEO | Change in Value of Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 6,064,560 | 42,129,404 | 46,885,010 | 28,071,620 | 15,982,957 |
| PEO | Fair Value of Unvested Equity Awards Granted in the Year [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 8,378,171 | 20,177,224 | 21,916,691 | 18,000,443 | 16,575,437 |
| PEO | Year-End Over Year-End Change in Fair Value of Unvested Equity Awards Granted in Prior Years [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 1,104,880 | 9,572,404 | 20,268,338 | 6,807,296 | 148,370 |
| PEO | Vesting Date Fair Value of Vested Equity Awards Granted in the Year [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 263,581 | 245,216 | 252,069 | 0 | 0 |
| PEO | Year-End Over Vesting Date Change in Fair Value of Vested Equity Awards Granted in Prior Years [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (4,176,225) | 11,406,939 | 3,595,977 | 2,324,862 | (1,527,886) |
| PEO | Fair Value at Prior Year-End of Equity Awards Cancelled in the Year [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 0 | 0 | 0 | 0 | 0 |
| PEO | Value of Dividends or Other Earnings on Equity Awards in the Year [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | $ 494,153 | 727,621 | 851,935 | 939,019 | 787,036 |
| Non-PEO NEO | Grant Date Fair Value of Equity-Based Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | (3,203,916) | (2,807,979) | (4,029,882) | (2,815,663) |
| Non-PEO NEO | Change in Pension Value [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | (192,840) | (82,922) | (100,517) | (493,663) |
| Non-PEO NEO | Pension Service Cost [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 104,741 | 94,246 | 99,299 | 164,855 |
| Non-PEO NEO | Change in Value of Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 8,368,736 | 9,106,786 | 4,860,130 | 2,617,776 |
| Non-PEO NEO | Fair Value of Unvested Equity Awards Granted in the Year [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 4,010,183 | 4,132,208 | 3,871,397 | 3,026,197 |
| Non-PEO NEO | Year-End Over Year-End Change in Fair Value of Unvested Equity Awards Granted in Prior Years [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 2,012,595 | 3,872,509 | 561,095 | 122,027 |
| Non-PEO NEO | Vesting Date Fair Value of Vested Equity Awards Granted in the Year [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 28,408 | 284,789 | 17,579 | 0 |
| Non-PEO NEO | Year-End Over Vesting Date Change in Fair Value of Vested Equity Awards Granted in Prior Years [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 2,140,847 | 764,776 | 648,226 | (628,062) |
| Non-PEO NEO | Fair Value at Prior Year-End of Equity Awards Cancelled in the Year [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 0 | (109,242) | (359,524) | 0 |
| Non-PEO NEO | Value of Dividends or Other Earnings on Equity Awards in the Year [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | $ 176,703 | $ 161,746 | $ 121,357 | $ 97,614 |
