Consolidated Statements Of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues and other income:
Sales of purchased oil and gas	$ 1,070	$ 316
Interest and other	18	13
Derivative gains (losses), net	(208)	151
Gain on disposition of assets, net	4	11
Total revenues and other income	2,150	1,300
Costs and expenses:
Oil and gas	1,266	809
Oil and gas production	213	141
Production and ad valorem taxes	76	47
Depletion, depreciation and amortization	357	337
Purchased oil and gas	1,054	335
Impairment of oil and gas properties	0	285
Exploration and abandonments	35	33
General and administrative	90	84
Accretion of discount on asset retirement obligations	4	5
Interest	36	46
Other	57	60
Costs and Expenses	1,922	1,373
Income (loss) before income taxes	228	(73)
Income tax benefit (provision)	(50)	31
Net income (loss) attributable to common stockholders	178	(42)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 178	$ (42)
Basic and diluted net income (loss) per share attributable to common stockholders (usd per share)	$ 1.04	$ (0.25)
Weighted average shares outstanding:
Weighted average shares, basic	170	170
Weighted average shares, diluted	171	170
Dividends declared per share (usd per share)	$ 0.16	$ 0.04