Exploratory Costs - Aging of Capitalized Exploratory Costs (Details) $ in Millions	Sep. 30, 2021 USD ($) Well	Dec. 31, 2020 USD ($) Well
Extractive Industries [Abstract]
One year or less	$ 750	$ 495
More than one year	0	3
Total	$ 750	$ 498
Number of wells or projects with exploratory well costs that have been suspended for a period greater than one year \| Well	0	1

No definition available.

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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://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

+ Details

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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

+ Details

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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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- 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

+ Details

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