Industry Segments (Details) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($) segment	Mar. 31, 2016 USD ($) segment
Segment Information
Number of operating segments \| segment	3	3
Net sales	$ 2,957	$ 2,123
Pre-tax operating profit (loss)	195	(563)
Income taxes	(78)	203
Discontinued operations, net		438
Net income (loss)	117	78
Operating segments \| Oil and Gas
Segment Information
Net sales	1,894	1,275
Pre-tax operating profit (loss)	220	(485)
Net income (loss)	220	(485)
Operating segments \| Chemical
Segment Information
Net sales	1,068	890
Pre-tax operating profit (loss)	170	214
Net income (loss)	170	214
Operating segments \| Midstream and Marketing
Segment Information
Net sales	211	133
Pre-tax operating profit (loss)	(47)	(95)
Net income (loss)	(47)	(95)
Corporate and Eliminations
Segment Information
Net sales	(216)	(175)
Pre-tax operating profit (loss)	(148)	(197)
Income taxes	(78)	203
Discontinued operations, net		438
Net income (loss)	$ (226)	$ 444

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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