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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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-Section 50
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-Name Accounting Standards Codification
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-Section 45
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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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 28
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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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.

+ References

No definition available.

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Properties, Plants and Equipment (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Property, Plant and Equipment [Line Items]
Impairments	$ 1,140	$ 853	$ 4,146	$ 856
San Francisco Refinery Asset Group
Property, Plant and Equipment [Line Items]
Impairments	1,030
Fair value of PP&E	940		$ 940
PP&E	1,009
Refining \| San Francisco Refinery Asset Group
Property, Plant and Equipment [Line Items]
PP&E	889
Intangible assets	21
Midstream
Property, Plant and Equipment [Line Items]
Impairments	204
Midstream \| San Francisco Refinery Asset Group
Property, Plant and Equipment [Line Items]
PP&E	$ 120