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
Oil sales	$ 1,567		$ 1,239	$ 4,652		$ 3,214
Natural-gas sales	269		435	1,090		1,121
Natural-gas liquids sales	265		227	768		640
Gathering, processing, and marketing sales	509		350	1,417		895
Gains (losses) on divestitures and other, net	(114)		(358)	1,052		(388)
Total	2,496		1,893	8,979		5,482
Costs and Expenses
Oil and gas operating	257		198	748		608
Oil and gas transportation	220		256	698		744
Exploration	751		304	2,371		506
Gathering, processing, and marketing	398		291	1,108		758
General and administrative	280		362	840		1,116
Depreciation, depletion, and amortization	1,083		1,069	3,235		3,202
Production, property, and other taxes	159		148	449		422
Impairments	0		27	383		61
Other operating expense	123		31	157		54
Total	3,271		2,686	9,989		7,471
Operating Income (Loss)	(775)		(793)	(1,010)		(1,989)
Other (Income) Expense
Interest expense	230		220	680		657
Loss on early extinguishment of debt	0		0	2		124
(Gains) losses on derivatives, net	82		24	(33)		634
Other (income) expense, net	(21)		(31)	(43)		(86)
Total	291		214	606		1,324
Income (Loss) Before Income Taxes	(1,066)		(1,007)	(1,616)		(3,313)
Income tax expense (benefit)	(425)		(260)	(366)		(957)
Net Income (Loss)	(641)		(747)	(1,250)		(2,356)
Net income (loss) attributable to noncontrolling interests	58	[1]	83	182	[1]	200
Net Income (Loss) Attributable to Common Stockholders	$ (699)		$ (830)	$ (1,432)		$ (2,556)
Per Common Share
Net income (loss) attributable to common stockholders—basic (in usd per share)	$ (1.27)		$ (1.61)	$ (2.60)		$ (5.00)
Net income (loss) attributable to common stockholders—diluted (in usd per share)	$ (1.27)		$ (1.61)	$ (2.61)		$ (5.00)
Average Number of Common Shares Outstanding—Basic	553		517	552		512
Average Number of Common Shares Outstanding—Diluted	553		517	552		512
Dividends (in usd per share)	$ 0.05		$ 0.05	$ 0.15		$ 0.15
Commodity Contract and Interest Rate Swap [Member]
Other (Income) Expense
(Gains) losses on derivatives, net	$ 82		$ 25	$ (33)		$ 629

[1] Presentation has been adjusted to align with the current analysis of segment performance. Net income (loss) attributable to noncontrolling interests, previously reported within the Midstream segment, is now presented within Other and Intersegment Eliminations. Other revenues, previously reported within Other and Intersegment Eliminations, is now presented within the applicable segments.