CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenues and Other
Natural-gas sales	$ 484	$ 830	$ 1,612	$ 3,038
Oil and condensate sales	1,229	2,637	4,264	7,766
Natural-gas liquids sales	183	424	644	1,221
Gathering, processing, and marketing sales	334	339	932	928
Gains (losses) on divestitures and other, net	(542)	780	(807)	2,340
Total	1,688	5,010	6,645	15,293
Costs and Expenses
Oil and gas operating	262	275	784	861
Oil and gas transportation and other	271	322	921	869
Exploration	1,074	199	2,260	1,000
Gathering, processing, and marketing	289	269	798	771
General and administrative	345	381	933	984
Depreciation, depletion, and amortization	1,111	1,163	3,581	3,335
Other taxes	127	306	460	981
Impairments	758	394	3,571	514
Total	4,237	3,312	13,312	9,411
Operating Income (Loss)	(2,549)	1,698	(6,667)	5,882
Other (Income) Expense
Interest expense	199	204	616	573
(Gains) losses on derivatives, net	281	(324)	123	462
Other (income) expense, net	47	24	109	12
Total	528	(76)	853	5,376
Income (Loss) Before Income Taxes	(3,077)	1,774	(7,520)	506
Income tax expense (benefit)	(917)	627	(2,232)	1,719
Net Income (Loss)	(2,160)	1,147	(5,288)	(1,213)
Net income attributable to noncontrolling interests	75	60	154	142
Net Income (Loss) Attributable to Common Stockholders	$ (2,235)	$ 1,087	$ (5,442)	$ (1,355)
Per Common Share
Net income (loss) attributable to common stockholders—basic	$ (4.41)	$ 2.13	$ (10.73)	$ (2.69)
Net income (loss) attributable to common stockholders—diluted	$ (4.41)	$ 2.12	$ (10.73)	$ (2.69)
Average Number of Common Shares Outstanding—Basic	508	506	508	505
Average Number of Common Shares Outstanding—Diluted	508	508	508	505
Dividends (per common share)	$ 0.27	$ 0.27	$ 0.81	$ 0.72
Commodity Contract and Interest Rate Swap [Member]
Other (Income) Expense
(Gains) losses on derivatives, net	$ 282	$ (323)	$ 123	$ 453
Deepwater Horizon [Member] | Pending Litigation [Member]
Costs and Expenses
Litigation-related contingent loss	0	3	4	96
Tronox Litigation [Member] | Judicial Ruling [Member]
Costs and Expenses
Litigation-related contingent loss	$ 0	$ 19	$ 5	$ 4,338