Dispositions - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) a	Dec. 31, 2014 USD ($) a
Disposition Of Businesses [Line Items]
Cash proceeds from asset sales	$ 140,000,000	$ 50,000,000	$ 2,978,000,000
Gains (loss) on asset sales, net	23,000,000	51,000,000	823,000,000
Gain (loss) on asset sale, after-tax			0
Interests in Pangkah Asset, Offshore Indonesia
Disposition Of Businesses [Line Items]
Cash proceeds from asset sales			650,000,000
Gains (loss) on asset sales, net			31,000,000
Gain (loss) on asset sale, after-tax			(10,000,000)
Interests in Thailand
Disposition Of Businesses [Line Items]
Cash proceeds from asset sales			805,000,000
Gains (loss) on asset sales, net			706,000,000
Gain (loss) on asset sale, after-tax			706,000,000
Joint Venture Interest in an Electric Generating Facility in Newark, New Jersey
Disposition Of Businesses [Line Items]
Cash proceeds from asset sales			320,000,000
Gains (loss) on asset sales, net			13,000,000
Gain (loss) on asset sale, after-tax			8,000,000
Joint Venture Interest in Bayonne Energy Center
Disposition Of Businesses [Line Items]
Cash proceeds from asset sales			79,000,000
Interest in an Exploration Asset in United Kingdom North Sea
Disposition Of Businesses [Line Items]
Cash proceeds from asset sales			53,000,000
Gains (loss) on asset sales, net			33,000,000
Gain (loss) on asset sale, after-tax			33,000,000
Interest in Algeria
Disposition Of Businesses [Line Items]
Gains (loss) on asset sales, net		(21,000,000)
Gain (loss) on asset sale, after-tax		(21,000,000)
Miscellaneous Non-core Assets
Disposition Of Businesses [Line Items]
Cash proceeds from asset sales	100,000,000
Gains (loss) on asset sales, net	23,000,000
Gain (loss) on asset sale, after-tax	$ 14,000,000
Net Acres in Utica Dry Gas Area of Utica Shale
Disposition Of Businesses [Line Items]
Cash proceeds from asset sales			1,075,000,000
Gains (loss) on asset sales, net		49,000,000	62,000,000
Gain (loss) on asset sale, after-tax		$ 31,000,000	$ 35,000,000
Net acres of Utica dry gas acreage sold | a		13,000	77,000
Sales price of Utica dry gas acreage sold		$ 120,000,000
Joint Venture Interest in Bayonne Energy Center
Disposition Of Businesses [Line Items]
Cash proceeds from asset sales		20,000,000
Gains (loss) on asset sales, net		20,000,000
Gain (loss) on asset sale, after-tax		$ 13,000,000