Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues and other income:
Sales and other operating revenues, including related party	$ 1,114	$ 781	$ 3,026	$ 2,032
Marketing revenues	48	80	117	202
Income from equity method investments	63	59	183	110
Net gain on disposal of assets	19	47	26	281
Other income	8	23	31	38
Total revenues and other income	1,252	990	3,383	2,663
Costs and expenses:
Production	194	160	521	532
Marketing, including purchases from related parties	49	80	121	201
Other operating	109	183	309	373
Exploration Expense	294	83	352	289
Depreciation, depletion and amortization	641	522	1,789	1,583
Impairments	201	47	205	48
Taxes other than income	44	35	128	113
General and administrative	97	104	299	386
Total costs and expenses	1,629	1,214	3,724	3,525
Income (loss) from operations	(377)	(224)	(341)	(862)
Net interest and other	(35)	(89)	(199)	(256)
Gain (Loss) on Extinguishment of Debt	(46)	0	(46)	0
Income from operations before income taxes	(458)	(313)	(586)	(1,118)
Provision (benefit) for income taxes	141	(107)	216	(414)
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	(599)	(206)	(802)	(704)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	0	14	(4,893)	(65)
Net income (loss)	$ (599)	$ (192)	$ (5,695)	$ (769)
Earnings Per Share, Basic [Abstract]
Income (loss) from continuing operations, per basic share	$ (0.70)	$ (0.24)	$ (0.94)	$ (0.87)
Income (loss) from discontinued operations, per basic share	0.00	0.01	(5.76)	(0.08)
Net income (loss), per basic share	(0.70)	(0.23)	(6.70)	(0.95)
Earnings Per Share, Diluted [Abstract]
Income (loss) from continuing operations, per diluted share	(0.70)	(0.24)	(0.94)	(0.87)
Income (loss) from discontinued operations, per diluted share	0.00	0.01	(5.76)	(0.08)
Net income (loss), per diluted share	(0.70)	(0.23)	(6.70)	(0.95)
Dividends paid, per share	$ 0.05	$ 0.05	$ 0.15	$ 0.15
Weighted average common shares outstanding:
Weighted average common shares outstanding, basic	850	847	850	809
Weighted average common shares outstanding, diluted	850	847	850	809