Debt - Summary of Outstanding Borrowings (Detail) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
Aug. 11, 2025 |
|---|---|---|---|
| Debt Instrument [Line Items] | |||
| Finance lease obligations | $ 6 | $ 6 | |
| Debt and Lease Obligation | 26,006 | 26,006 | |
| Unamortized debt issuance costs | (185) | (174) | |
| Unamortized discount | (187) | (179) | |
| Amounts due within one year | 1,251 | 1,502 | |
| Total long-term debt due after one year | 24,383 | 24,151 | |
| Senior Notes [Member] | |||
| Debt Instrument [Line Items] | |||
| Debt Instrument, Face Amount | $ 4,500 | ||
| MPLX LP [Member] | |||
| Debt Instrument [Line Items] | |||
| Senior Notes | 25,969 | 25,969 | |
| ANDX LP [Member] | |||
| Debt Instrument [Line Items] | |||
| Senior Notes | $ 31 | $ 31 |
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- Definition Amount of short-term and long-term debt and lease obligation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after accumulated amortization, of debt discount. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of long-term debt and lease obligation, classified as noncurrent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of long-term debt and lease obligation, classified as current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. No definition available.
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