Basis of Presentation and Significant Accounting Policies (Details) bbl / d in Millions, $ in Millions, gal / yr in Billions	12 Months Ended
Dec. 31, 2015 USD ($) gal / yr bbl / d refineries plants branded_wholesale_sites	Dec. 31, 2014 USD ($)
Basis of Presentation and Summary of Significant Accounting Policies (Textual)
Number of refineries owned \| refineries	15
Combined total throughput capacity of petroleum refining (barrels per day) \| bbl / d	3.0
Number of branded wholesale sites \| branded_wholesale_sites	7,500
Number of ethanol plants owned \| plants	11
Combined capacity of ethanol (gallons per year) \| gal / yr	1.4
New Accounting Pronouncements (Textual)
Current deferred income tax assets	$ 74	$ 162
Current deferred income tax liabilities	366	$ 376
Issued Debt [Member]
New Accounting Pronouncements (Textual)
Debt issuance costs associated with issued debt	$ 42
Minimum [Member]
Basis of Presentation and Summary of Significant Accounting Policies (Textual)
Property, plant, and equipment, useful life	25 years
Maximum [Member]
Basis of Presentation and Summary of Significant Accounting Policies (Textual)
Property, plant, and equipment, useful life	30 years

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards expected to be realized or consumed within one year or operating cycle, if longer.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Combined capacity of ethanol (gallons per year)

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Combined total throughput capacity of petroleum refining.

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Number of branded wholesale sites that sell our refined products.

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Number of Ethanol Plants Owned by Company.

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Total number of refineries owned by Valero.

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Summary of Significant Accounting Policies, Textual [Abstract]

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