Exploratory Well and Project Costs - Aging of Capitalized Exploratory Costs (Details) $ in Millions	Dec. 31, 2021 USD ($) Well	Dec. 31, 2020 USD ($) Well	Dec. 31, 2019 USD ($) Well
Capitalized Exploratory Well Costs [Abstract]
One year or less	$ 621	$ 495	$ 660
More than one year	11	3	0
Total	$ 632	$ 498	$ 660
Number of projects with exploratory well costs that have been suspended for a period greater than one year (a) \| Well	3	1	0

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123377692&loc=SL6806780-109447

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- References

No definition available.

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- Definition

The amount of exploratory well costs that have been capitalized for a period of greater than one year after the completion of drilling.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=123377692&loc=SL6806780-109447

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- Definition

The amount of exploratory well costs that have been capitalized for a period of one year or less after the completion of drilling.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

The number of projects for which exploratory well costs have been capitalized for a period of greater than one year after the completion of drilling.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=123377692&loc=SL6806780-109447

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