Accounting For Suspended Exploratory Well Costs (Change In Capitalized Suspended Exploratory Well Costs) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Oil and Gas, Capitalized Exploratory Well Cost [Roll Forward]
Balance beginning at January 1	$ 3,559	$ 3,512	$ 4,120
Additions pending the determination of proved reserves	453	200	378
Charged to expense	(69)	(95)	(259)
Reclassifications to wells, facilities and equipment based on the determination of proved reserves	(292)	(142)	(142)
Divestments/Other	(51)	84	(585)
Ending balance at December 31	3,600	3,559	3,512
Ending balance attributed to equity companies included above	$ 225	$ 306	$ 306

Amount of addition to capitalized exploratory well cost pending determination of proved reserve in oil- and gas-producing activities.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 932
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477215/932-235-50-1B

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of expense for capitalized exploratory well costs for which proved reserves were not found at the exploratory well.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 932
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477215/932-235-50-1B

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- Definition

The amount of capitalized exploratory well costs that is pending the determination of proved reserves. This does not include amounts that were capitalized and subsequently expensed in the same annual period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 932
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477215/932-235-50-1B

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of reclassification of capitalized exploratory well cost to well, facility, and equipment based on determination of proved reserve in oil- and gas-producing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 932
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477215/932-235-50-1B

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- Definition

Capitalized Exploratory Well Costs Attributable To Equity Companies

+ References

No definition available.

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- Definition

Previously capitalized costs of the drilling of wells that were related to assets that were divested or otherwise removed from capitalized costs.

+ References

No definition available.

+ Details

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