Statement of Consolidated Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Oil and gas production revenues
Oil and Gas Production Revenues	$ 1,386	$ 1,991	$ 2,473	$ 3,650
Other	(21)	28	(24)	22
Gain on divestitures	17	227	16	209
Total revenues and other	1,382	2,246	2,465	3,881
OPERATING EXPENSES:
Lease operating expenses	359	467	737	948
Gathering and transportation	52	49	104	105
Taxes other than income	65	55	76	128
Exploration	91	225	186	483
General and administrative	103	111	196	195
Depreciation, depletion, and amortization:
Depreciation, depletion and amortization	669	794	1,347	1,620
Asset retirement obligation accretion	38	36	76	72
Impairments	173	512	173	2,424
Transaction, reorganization, and separation	9	66	24	120
Financing costs, net	104	117	209	241
Total operating expenses	1,663	2,432	3,128	6,336
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(281)	(186)	(663)	(2,455)
Current income tax provision	144	900	134	848
Deferred income tax benefit	(225)	(169)	(226)	(1,318)
NET LOSS FROM CONTINUING OPERATIONS INCLUDING NONCONTROLLING INTEREST	(200)	(917)	(571)	(1,985)
Net income (loss) from discontinued operations, net of tax	0	120	0	(118)
NET LOSS INCLUDING NONCONTROLLING INTEREST	(200)	(797)	(571)	(2,103)
Net income attributable to noncontrolling interest	44	63	45	91
NET LOSS ATTRIBUTABLE TO COMMON STOCK	(244)	(860)	(616)	(2,194)
NET LOSS ATTRIBUTABLE TO COMMON SHAREHOLDERS:
Net loss from continuing operations attributable to common shareholders	(244)	(980)	(616)	(2,076)
Net income (loss) from discontinued operations	0	120	0	(118)
NET LOSS ATTRIBUTABLE TO COMMON STOCK	$ (244)	$ (860)	$ (616)	$ (2,194)
NET LOSS PER COMMON SHARE:
Basic net loss from continuing operations per share	$ (0.65)	$ (2.60)	$ (1.63)	$ (5.50)
Basic net loss from discontinued operations per share	0.00	0.32	0.00	(0.31)
Basic net loss per share	(0.65)	(2.28)	(1.63)	(5.81)
DILUTED NET LOSS PER COMMON SHARE:
Diluted net loss from continuing operations per share	(0.65)	(2.60)	(1.63)	(5.50)
Diluted net loss from discontinued operations per share	0.00	0.32	0.00	(0.31)
Diluted net loss per share	$ (0.65)	$ (2.28)	$ (1.63)	$ (5.81)
WEIGHTED-AVERAGE NUMBER OF COMMON SHARES OUTSTANDING:
Basic (in shares)	379	378	379	377
Diluted (in shares)	379	378	379	377
DIVIDENDS DECLARED PER COMMON SHARE	$ 0.25	$ 0.25	$ 0.5	$ 0.5
Oil and gas property and equipment [Member]
Depreciation, depletion, and amortization:
Depreciation, depletion and amortization	$ 629	$ 711	$ 1,265	$ 1,454
Other assets [Member]
Depreciation, depletion, and amortization:
Depreciation, depletion and amortization	40	83	82	166
Oil [Member]
Oil and gas production revenues
Oil and Gas Production Revenues	1,118	1,618	1,940	2,911
Gas [Member]
Oil and gas production revenues
Oil and Gas Production Revenues	209	315	432	623
Natural gas liquids [Member]
Oil and gas production revenues
Oil and Gas Production Revenues	$ 59	$ 58	$ 101	$ 116