Inventories (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Schedule of Inventories
Refinery feedstocks	$ 2,574		$ 2,404
Refined products and blendstocks	3,424		3,774
Ethanol feedstocks and products	264		242
Materials and supplies	249		244
Inventories, before lower of cost or market inventory valuation reserve	6,511		6,664
Lower of cost or market inventory valuation reserve	(455)		(766)
Inventories	6,056		5,898
Inventories (Textual)
Lower of cost or market inventory valuation adjustment	(293)	$ 0
Amount of non-LIFO inventory	$ 685		$ 668

The aggregate carrying amount as of the balance sheet date of unrefined petroleum and the liquid hydrocarbon components recovered from natural gas.

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Carrying amount as of the balance sheet date of finished goods inventories for petroleum products, crude oil, petrochemical products, and other oil and gas inventories.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Amount of valuation reserve for inventory.

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Charge to cost of goods sold that represents the reduction of the carrying amount of inventory, generally attributable to obsolescence or market conditions.

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The amount of weighted average cost inventory present at the reporting date when inventory is valued using different valuation methods.

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Carrying amount as of the balance sheet date of ethanol feedstocks and products.

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Inventories, Textual [Abstract]

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Amount of inventory net of LIFO reserves, but before valuation reserves, expected to be sold, or consumed within one year or operating cycle, if longer.

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No definition available.

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