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Equity Method Investments - Whistler Joint Venture Transaction - (Details) - USD ($) $ in Millions |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
May 29, 2024 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | May 28, 2024
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Gain (loss) on disposition of stock in subsidiary or equity method investee | [1] |  | $ 0 | $ 106 | $ 151 | $ 106 |
Investments - redemptions, repayments, return of capital and sales proceeds |  |  |  |  | $ 141 | $ 270 |
Whistler Pipeline, LLC | MPLX |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Ownership percentage |  |  |  |  |  |  | 37.50%
WPC Parent, LLC |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Gain (loss) on disposition of stock in subsidiary or equity method investee |  | $ 151 |  |  |  |  |
Investments - redemptions, repayments, return of capital and sales proceeds |  | $ 134 |  |  |  |  |
WPC Parent, LLC | Enbridge Inc. |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Ownership percentage |  | 19.00% |  |  |  |  |
WPC Parent, LLC | MPLX |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Ownership percentage |  | 30.40% |  |  |  |  |
[1] | The first nine months of 2024 includes the gain from the Whistler Joint Venture Transaction (as defined in Note 13). 2023 includes the gain on the sale of our interest in South Texas Gateway Terminal LLC. See Note 13 for additional information.

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