Previously capitalized costs of the drilling of wells that were sold in the period and other items.

No definition available.

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- Definition

Additions to capitalized exploratory well costs that were added during the reporting period pending the determination of proved reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6806780-109447

+ Details

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- 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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6806780-109447

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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6806780-109447

+ Details

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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

Previously capitalized costs of the drilling of wells that were reclassified as part of the costs of the enterprise's wells and related equipment and facilities at the time that proved reserves were found.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6806780-109447

+ Details

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Suspended Exploratory Well Costs - Rollforward (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Balance at January 1		$ 1,230	$ 1,124	$ 1,522
Additions pending the determination of proved reserves		349	490	461
Divestitures and other		(36)	(11)	(33)
Reclassifications to proved properties		(41)	(50)	(104)
Charges to exploration expense		(977)	(323)	(722)
Balance at December 31		525	1,230	1,124
Exploration and Production Reporting Segment [Member] \| Gulf Of Mexico, Shenandoah Project [Member]
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Balance at January 1		326
Charges to exploration expense		(437)
Balance at December 31			326
Exploration and Production Reporting Segment [Member] \| Gulf Of Mexico, Phobos Project [Member]
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Balance at January 1		99
Charges to exploration expense	$ (215)
Balance at December 31			99
Exploration and Production Reporting Segment [Member] \| Gulf Of Mexico, Warrior Project [Member]
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Charges to exploration expense	$ (108)
Exploration and Production Reporting Segment [Member] \| Colombia Project [Member]
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Balance at January 1		102
Charges to exploration expense		(243)
Balance at December 31			102
Exploration and Production Reporting Segment [Member] \| Cote d’Ivoire Project [Member]
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Balance at January 1		237
Charges to exploration expense		$ (329)
Balance at December 31			237
Exploration and Production Reporting Segment [Member] \| Gulf of Mexico, Yeti Project [Member]
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Charges to exploration expense			(231)
Exploration and Production Reporting Segment [Member] \| Mozambique Project [Member]
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Charges to exploration expense			$ (92)
Exploration and Production Reporting Segment [Member] \| Brazil Project [Member]
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Charges to exploration expense				$ (565)