Supplementary Cash Flow Information (Detail) - USD ($) $ in Millions		12 Months Ended
	Jul. 01, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash Flows From Operating Activities
Interest paid		$ (338)	$ (331)	$ (326)
Net income taxes (paid) refunded		132	(140)	(455)
Cash Flows From Investing Activities
Capital expenditures incurred - E&P		(1,645)	(3,753)	(4,920)
(Increase) decrease in related liabilities – E&P		(334)	(203)	53
Additions to property, plant and equipment - E&P		(1,979)	(3,956)	(4,867)
Capital expenditures incurred - Bakken Midstream		(276)	(296)	(301)
(Increase) decrease in related liabilities – Bakken Midstream		4	(69)	(46)
Additions to property, plant and equipment - Bakken Midstream		(272)	(365)	(347)
Cash Flows From Financing Activities
Contribution from formation of Bakken Midstream joint venture	$ 2,628	0	2,628	0
Distributions to partner in Bakken Midstream joint venture		(23)	(332)	0
Noncontrolling interests, net related to Continuing operations		(23)	2,296	0
Significant Non-Cash Transactions
Increase in debt due to construction of a floating production system - Tubular Bells Field		$ 0	$ 0	$ 68