Divestitures - Dispositions and Divestitures (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017
Dispositions
Proceeds from sales of assets		$ 1,298	$ 407
Gain on sale of investment in unconsolidated entities	$ 210	210
Depreciation and amortization
Dispositions
Recognized gains/(losses) related to sale of assets, net	$ 2	79
Recognized gains related to sale of assets		105
Recognized losses related to sale of assets		$ 26
BridgeTex Pipeline Company, LLC
Dispositions
Interest percentage sold	30.00%	30.00%
Proceeds from sale of interest	$ 868
Ownership percentage	20.00%	20.00%
Gain on sale of investment in unconsolidated entities	$ 210

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of gain (loss) on sale or disposal of an equity method investment.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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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.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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