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- Definition

Maximum Exposure, Undiscounted, Co-venturers

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Maximum Loan, Amount with Co-venturers

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Percentage Of Ownership

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- Definition

Variable Interest Entity, Reporting Entity Involvement, Book Value Of Investment, Maximum Exposure, Amount

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Variable Interest Entity, Reporting Entity Involvement, Maximum Loan, Amount, Co-venture

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Face (par) amount of debt instrument at time of issuance.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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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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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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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 reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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Investments, Loans and Long-Term Receivables (Narrative) (Details) - USD ($)	2 Months Ended
	Feb. 28, 2019	Apr. 01, 2019	Mar. 31, 2019	Mar. 29, 2019	Dec. 31, 2018	Mar. 01, 2018
Gray Oak Pipeline LLC
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest			65.00%		75.00%
OnCue Holdings LLC
Schedule of Equity Method Investments [Line Items]
Percentage of ownership			50.00%
Maximum loss exposure			$ 124,000,000
Book value of investment			70,000,000
Maximum potential amount of future payments under the guarantees			54,000,000
Dakota Access and ETCO
Schedule of Equity Method Investments [Line Items]
Maximum exposure, undiscounted, co-venturers			2,525,000,000
Third Party \| Gray Oak Pipeline LLC
Schedule of Equity Method Investments [Line Items]
Percentage of ownership	10.00%
Gray Oak Pipeline LLC
Schedule of Equity Method Investments [Line Items]
Maximum loan, amount with co-ventures				$ 1,230,000,000
Subsequent Event \| Gray Oak Pipeline LLC
Schedule of Equity Method Investments [Line Items]
Due to related parties		$ 125,000,000
Senior Notes
Schedule of Equity Method Investments [Line Items]
Debt issued and guaranteed						$ 1,500,000,000
Senior Notes \| Dakota Access, LLC
Schedule of Equity Method Investments [Line Items]
Debt issued and guaranteed			2,500,000,000
Variable Interest Entity, Primary Beneficiary \| Phillips 66 Partners LP \| Dakota Access and ETCO
Schedule of Equity Method Investments [Line Items]
Maximum exposure, undiscounted			631,000,000
Variable Interest Entity, Primary Beneficiary \| Phillips 66 Partners LP \| Gray Oak Pipeline LLC
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of equity method investments	$ 81,000,000
Maximum loss exposure			771,000,000
Book value of investment			741,000,000
Maximum potential amount of future payments under the guarantees			$ 30,000,000
Maximum loan, amount				$ 520,000,000
Variable Interest Entity, Primary Beneficiary \| Subsequent Event \| Phillips 66 Partners LP \| Gray Oak Pipeline LLC
Schedule of Equity Method Investments [Line Items]
Due from related parties		$ 53,000,000