Earnings Per Common Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Earnings per common share from continuing operations:
Net income attributable to Valero stockholders from continuing operations	$ 964	$ 829
Less dividends paid:
Weighted-average common shares outstanding (in shares)	513	531
Earnings per common share from continuing operations:
Total earnings per common share from continuing operations (in usd per share)	$ 1.87	$ 1.55
Earnings per common share from continuing operations – assuming dilution:
Net income attributable to Valero stockholders from continuing operations	964	829
Weighted-average common shares outstanding (in shares)	513	531
Common equivalent shares:
Weighted-average common shares outstanding – assuming dilution (in shares)	516	536
Earnings per common share from continuing operations – assuming dilution (in usd per share)	$ 1.87	$ 1.54
Common Stock [Member]
Earnings per common share from continuing operations:
Net income attributable to Valero stockholders from continuing operations	964	829
Less dividends paid:
Common stock	205	132
Participating securities	1	1
Undistributed earnings	758	696
Weighted-average common shares outstanding (in shares)	513	531
Earnings per common share from continuing operations:
Distributed earnings (in usd per share)	$ 0.40	$ 0.25
Undistributed earnings (in usd per share)	$ 1.47	$ 1.30
Total earnings per common share from continuing operations (in usd per share)	$ 1.87	$ 1.55
Earnings per common share from continuing operations – assuming dilution:
Net income attributable to Valero stockholders from continuing operations	$ 964	$ 829
Weighted-average common shares outstanding (in shares)	513	531
Common equivalent shares:
Stock options (in shares)	2	3
Performance awards and nonvested restricted stock (in shares)	1	2
Weighted-average common shares outstanding – assuming dilution (in shares)	516	536
Earnings per common share from continuing operations – assuming dilution (in usd per share)	$ 1.87	$ 1.54
Participating Securities [Member]
Less dividends paid:
Weighted-average common shares outstanding (in shares)	2	2
Earnings per common share from continuing operations:
Distributed earnings (in usd per share)	$ 0.40	$ 0.25
Undistributed earnings (in usd per share)	$ 1.47	$ 1.30
Total earnings per common share from continuing operations (in usd per share)	$ 1.87	$ 1.55
Earnings per common share from continuing operations – assuming dilution:
Weighted-average common shares outstanding (in shares)	2	2

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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The earnings attributable to each security on the basis that all of the earnings for the period had been distributed (to the extent that each security may share in earnings). This is the earnings amount which reflects the participation rights in undistributed earnings of each security.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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