CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues and Other
Oil and condensate sales	$ 1,239	$ 1,229	$ 3,214	$ 4,264
Natural-gas sales	435	484	1,121	1,612
Natural-gas liquids sales	227	183	640	644
Gathering, processing, and marketing sales	350	334	895	932
Gains (losses) on divestitures and other, net	(358)	(542)	(388)	(807)
Total	1,893	1,688	5,482	6,645
Costs and Expenses
Oil and gas operating	198	262	608	784
Oil and gas transportation	256	265	744	853
Exploration	304	1,074	506	2,260
Gathering, processing, and marketing	291	289	758	798
General and administrative	362	303	1,116	888
Depreciation, depletion, and amortization	1,069	1,111	3,202	3,581
Other taxes	148	127	422	460
Impairments	27	758	61	3,571
Other operating expense	31	48	54	117
Total	2,686	4,237	7,471	13,312
Operating Income (Loss)	(793)	(2,549)	(1,989)	(6,667)
Other (Income) Expense
Interest expense	220	199	657	616
Loss on early extinguishment of debt	0	0	124	0
(Gains) losses on derivatives, net	24	281	634	123
Other (income) expense, net	(31)	47	(86)	109
Total	214	528	1,324	853
Income (Loss) Before Income Taxes	(1,007)	(3,077)	(3,313)	(7,520)
Income tax expense (benefit)	(260)	(917)	(957)	(2,232)
Net Income (Loss)	(747)	(2,160)	(2,356)	(5,288)
Net income (loss) attributable to noncontrolling interests	83	75	200	154
Net Income (Loss) Attributable to Common Stockholders	$ (830)	$ (2,235)	$ (2,556)	$ (5,442)
Per Common Share
Net income (loss) attributable to common stockholders—basic	$ (1.61)	$ (4.41)	$ (5.00)	$ (10.73)
Net income (loss) attributable to common stockholders—diluted	$ (1.61)	$ (4.41)	$ (5.00)	$ (10.73)
Average Number of Common Shares Outstanding—Basic	517	508	512	508
Average Number of Common Shares Outstanding—Diluted	517	508	512	508
Dividends (per common share)	$ 0.05	$ 0.27	$ 0.15	$ 0.81
Tronox Litigation [Member] | Judicial Ruling [Member]
Other (Income) Expense
Tronox-related contingent loss	$ 0	$ 0	$ 0	$ 5
Commodity Contract and Interest Rate Swap [Member]
Other (Income) Expense
(Gains) losses on derivatives, net	$ 25	$ 282	$ 629	$ 123