Condensed Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
REVENUES AND OTHER
Oil and gas net sales	$ 439	$ 404	$ 926	$ 733
Net derivative gains (losses)	43	(118)	116	(143)
Other revenue	34	31	64	49
Total revenues and other	516	317	1,106	639
COSTS AND OTHER
Production costs	216	188	427	372
General and administrative expenses	61	61	128	128
Depreciation, depletion and amortization	138	138	278	285
Taxes other than on income	31	42	64	81
Exploration expense	6	5	12	10
Other expenses, net	25	24	47	47
Total costs and other	477	458	956	923
OPERATING INCOME (LOSS)	39	(141)	150	(284)
NON-OPERATING INCOME (LOSS)
Interest and debt expense, net	(83)	(74)	(167)	(148)
Net gains on early extinguishment of debt		(44)	(4)	(133)
Gains on asset divestitures		31	21	31
Other non-operating expense	(3)	0	(3)	0
(LOSS) INCOME BEFORE INCOME TAXES	(47)	(140)	5	(268)
Income tax benefit				78
NET (LOSS) INCOME	(47)	(140)	5	(190)
Net income attributable to noncontrolling interest	(1)
NET (LOSS) INCOME ATTRIBUTABLE TO COMMON STOCK	$ (48)	$ (140)	$ 5	$ (190)
(Loss) Earnings per share of common stock
Basic (in dollars per share)	$ (1.13)	$ (3.51)	$ 0.12	$ (4.85)
Diluted (in dollars per share)	$ (1.13)	$ (3.51)	$ 0.12	$ (4.85)