Equity Method Investment, Decline In Market Value, Percent

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Equity Method Investment, Number Of Joint Ventures Impaired

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Impairments - Narrative (Details) $ in Millions	3 Months Ended						12 Months Ended
Impairments - Narrative (Details) $ in Millions	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($) joint_venture	Sep. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges							$ 1,498	$ 4,252	$ 861
Goodwill impairment								1,845
Refining
Impaired Long-Lived Assets Held and Used [Line Items]
Goodwill impairment					$ 1,845			1,845
Midstream
Impaired Long-Lived Assets Held and Used [Line Items]
Goodwill impairment								$ 0
Alliance Refinery
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges	$ 1,298
Fair value of PP&E	200
Alliance Refinery \| Refining
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges	1,288
Alliance Refinery \| Midstream
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges	$ 10
San Francisco Refinery Asset Group
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges				$ 1,030
Fair value of PP&E				940
PP&E impairment				1,009
San Francisco Refinery Asset Group \| Refining
Impaired Long-Lived Assets Held and Used [Line Items]
Intangible assets impairment, excluding goodwill				21
San Francisco Refinery Asset Group \| Midstream
Impaired Long-Lived Assets Held and Used [Line Items]
PP&E impairment				120
Liberty Pipeline, LLC \| Phillips 66 Partners LP \| Variable Interest Entity, Primary Beneficiary
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges		$ 198
Red Oak Pipeline, LLC
Impaired Long-Lived Assets Held and Used [Line Items]
Equity method investment impairment				$ 84
Phillips 66 Partners Terminal And STACK Pipeline \| Phillips 66 Partners LP \| Variable Interest Entity, Primary Beneficiary
Impaired Long-Lived Assets Held and Used [Line Items]
Equity method investment impairment			$ 96
Number of joint ventures impaired \| joint_venture			2
DCP Midstream
Impaired Long-Lived Assets Held and Used [Line Items]
Equity method investment impairment					$ 1,161	$ 853
DCP Midstream \| DCP Partners
Impaired Long-Lived Assets Held and Used [Line Items]
Equity method investment, decline in market value, percent					85.00%