Supplemental Cash Flow Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Loss Contingencies [Line Items]
Interest, net of amounts capitalized (1)	$ 1,532	[1]	$ 265
Income taxes, net of refunds	(5)		598
Non-cash investing activities
Fair value of properties and equipment from non-cash transactions	54		0
Asset retirement cost additions	63		47
Accruals of property, plant, and equipment	1,061		1,544
Net liabilities assumed (divested) in acquisitions and divestitures	19		(25)
Non-cash investing and financing activities
Floating production, storage, and offloading vessel construction period obligation	18		34
Tronox Litigation [Member] | Judicial Ruling [Member]
Loss Contingencies [Line Items]
Deferred tax benefit related to the Tronox settlement	577
Interest, net of amounts capitalized (1)	1,200
Other Assets [Member] | Tronox Litigation [Member] | Judicial Ruling [Member]
Loss Contingencies [Line Items]
Deferred tax benefit related to the Tronox settlement	$ 561

[1] Includes $1.2 billion of interest related to the Tronox settlement payment in 2015.