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Equity Method Investments (Details) - USD ($) $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2019 | Sep. 30, 2018
Contribution of net assets to Capline LLC |  | $ 143 | [1] | $ 0
Recognition of Capline LLC equity method investment |  | $ 350 | [1] | $ 0
Capline |  |  |  |
Undivided joint interest, ownership percentage |  | 33.00% |  |
Equity method investments, ownership percentage |  | 33.00% |  |
Contribution of net assets to Capline LLC | [1] | $ 143 |  |
Recognition of Capline LLC equity method investment | [1] | 350 |  |
Capline restructuring gain | [1] | $ 207 |  |
[1] | See Note 13.

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