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Acquisitions and Other Transactions (MarkWest Torñado GP, L.L.C.) (Details) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Dec. 15, 2023 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Business Combination [Line Items] |  |  |  |
Contract with Customer, Asset, before Allowance for Credit Loss, Noncurrent |  | $ 4 | $ 0 | $ 1
Equity method investments |  | 4,798 | 4,531 |
Equity Interest in Acquiree, Remeasurement Gain |  | $ 484 | $ 20 | $ 92
MarkWest Tornado GP, L.L.C. |  |  |  |
Business Combination [Line Items] |  |  |  |
Equity Method Investment, Remaining Ownership Interest Purchased | 40.00% |  |  |
Payments to Acquire Additional Interest in Subsidiaries | $ 303 |  |  |
Payments to Acquire Businesses, Gross | 270 |  |  |
Contract with Customer, Asset, before Allowance for Credit Loss, Noncurrent | $ 33 |  |  |
Business Combination, Achieved in Stages, Preacquisition and Acquired Equity Interests in Acquiree, Percentage | 100.00% |  |  |
Equity Interest in Acquiree, Percentage | 60.00% |  |  |
Equity method investments | $ 311 |  |  |
Equity Interest in Acquiree, Remeasurement Gain | 92 |  |  |
Recognized Identifiable Assets Acquired and Liabilities Assumed, Net | $ 673 |  |  |

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