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

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

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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

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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

No definition available.

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Property, Plant and Equipment (Details 3) $ in Millions	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Projects that have Exploratory Well Costs that have been Capitalized for Period Greater than One Year, Number of Projects	3	2	3
Amounts capitalized greater than one year after completion of drilling	$ 118	$ 85	$ 126
GABON
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Amounts capitalized greater than one year after completion of drilling	64
EQUATORIAL GUINEA
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Amounts capitalized greater than one year after completion of drilling	$ 54