Exploratory Costs (Tables)

6 Months Ended

Jun. 30, 2017

Exploratory Cost Disclosure [Abstract]

Capitalized exploratory well and project activity

The following table reflects the Company's capitalized exploratory well and project activity during the three and six months ended June 30, 2017:

	Three Months Ended June 30, 2017			Six Months Ended June 30, 2017
	(in millions)
Beginning capitalized exploratory well costs	$	432		$	323
Additions to exploratory well costs pending the determination of proved reserves	489			895
Reclassification due to determination of proved reserves	(477		)	(765		)
Exploratory well costs charged to exploration and abandonment expense	(1		)	(10		)
Ending capitalized exploratory well costs	$	443		$	443

Capitalized Exploratory Costs And The Number Of Projects For Which Exploratory Costs Have Been Capitalized

The following table provides an aging as of June 30, 2017 and December 31, 2016 of capitalized exploratory costs and the number of projects for which exploratory well costs have been capitalized for a period greater than one year, based on the date drilling was completed:

	June 30, 2017		December 31, 2016
	(in millions, except well counts)
Capitalized exploratory well costs that have been suspended:
One year or less	$	420	$	318
More than one year	23		5
	$	443	$	323
Number of wells or projects with exploratory well costs that have been suspended for a period greater than one year	12		3