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v3.25.1

Senior Notes (Details) - Senior Notes [Member] - USD ($) $ in Millions | Apr. 09, 2025 | Mar. 10, 2025 | Feb. 18, 2025 | Mar. 31, 2025
--- | --- | --- | --- | ---
Senior Notes Due February 2025 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  | 4.00% |
Repayments of Debt |  |  | $ 500 |
Senior Note Due June 2035 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 5.40% |  |
Percent of Par |  | 99.398% |  |
Debt Instrument, Face Amount |  | $ 1,000 |  |
Debt Instrument, Issuance Date |  | Mar. 10, 2025 |  |
Senior Note Due June 2055 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 5.95% |  |
Percent of Par |  | 98.331% |  |
Debt Instrument, Face Amount |  | $ 1,000 |  |
Debt Instrument, Issuance Date |  | Mar. 10, 2025 |  |
Senior Notes Due June 2025 | Subsequent Event |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Repayments of Debt | $ 1,200 |  |  |
Senior Notes Due June 2025 | MPLX LP [Member] | Subsequent Event |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.875% |  |  |
Repayments of Debt | $ 1,189 |  |  |
Senior Notes Due June 2025 | MarkWest [Member] | Subsequent Event |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.875% |  |  |
Repayments of Debt | $ 11 |  |  |
Minimum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  | 1.75%
Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  | 5.95%

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