Acquisition, Estimated Fair Values of Assets Acquired and Liabilities Assumed (Details) - Pure Biofuels [Member] $ in Millions	May 14, 2018 USD ($)
Fair Values of Assets Acquired, Goodwill, and Liabilities Assumed, Net
Current assets, net of cash acquired	$ 147
Property, plant, and equipment	137
Deferred charges and other assets	451
Current liabilities, excluding current portion of debt	(25)
Debt assumed, including current portion	(137)
Deferred income tax liabilities	(81)
Other long-term liabilities	(21)
Total consideration, net of cash acquired	$ 471

Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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