Inventories (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
Schedule of Inventories
Refinery feedstocks	$ 2,135us-gaap_CrudeOilAndNaturalGasLiquids		$ 2,269us-gaap_CrudeOilAndNaturalGasLiquids
Refined products and blendstocks	3,231		3,926
Ethanol feedstocks and products	166vlo_EthanolFeedstocksAndProducts		195vlo_EthanolFeedstocksAndProducts
Materials and supplies	226		233
Inventories	5,758us-gaap_InventoryNet		6,623us-gaap_InventoryNet
Inventories (Textual)
Effect of LIFO inventory liquidation on income, decrease	17	134
Excess of market value over carrying amount of LIFO inventories	6,900		857
Inventory not valued at LIFO	$ 681		$ 906

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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The effect of liquidating LIFO (last in first out) inventory layers on income.

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The excess of replacement or current cost over the stated LIFO (last in first out) inventory value when the LIFO inventory method is utilized.

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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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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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No definition available.

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