Derivatives and Financial Instruments - Schedule of Outstanding Commodity Derivative Contracts (Details) bbl in Millions, Bcf in Billions	3 Months Ended	12 Months Ended
Mar. 31, 2026 bbl Bcf	Dec. 31, 2025 bbl Bcf
Derivative [Line Items]
Percentage of derivative contract volume expiring within twelve months	90.00%	90.00%
Short \| Commodity Derivative Assets \| Crude oil, refined petroleum products, NGL and renewable feedstocks (millions of barrels)
Derivative [Line Items]
Commodity \| bbl	(53)	(33)
Short \| Commodity Derivative Assets \| Natural gas (billions of cubic feet)
Derivative [Line Items]
Commodity \| Bcf	(14)	(17)

Estimated percentage of derivative contract volume expiring within twelve months

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- Definition

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

+ Details

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- Details

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- Details

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- Details

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