Contingencies (Detail) (USD $)	12 Months Ended					12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Landfill in West Covina, California [Member]	Mar. 31, 2012 Algeria Exceptional Profits Tax Settlement [Member]	Dec. 31, 2013 Third Party Bankruptcy Assignment [Member]	Dec. 31, 2013 Pending Litigation [Member] Peregrino Litigation [Member]	Dec. 31, 2013 Pending Litigation [Member] Peregrino Litigation [Member] Amount Of Tax Originally In Dispute [Member]	Dec. 31, 2013 Pending Litigation [Member] Peregrino Litigation [Member] Amount Of Tax Currently In Dispute [Member]
Loss Contingencies [Line Items]
Loss contingency accrual	$ 854,000,000	$ 49,000,000					$ 0
Other Assets	2,082,000,000	1,716,000,000						144,000,000	47,000,000
Algeria exceptional profits tax settlement	0	730,000,000			1,700,000,000
Decommissioning charge	850,000,000	(250,000,000)	250,000,000			117,000,000
Decommissioning obligations included in accrued expenses						21,000,000
Decommissioning obligations included in other long-term liabilities	850,000,000	0				85,000,000
Liability for remediation and reclamation obligations	$ 126,000,000	$ 81,000,000		$ 50,000,000