Earnings Per Common Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Less dividends paid:
Weighted-average common shares outstanding (in millions)	540	549	544	550
Earnings per common share – assuming dilution:
Weighted-average common shares outstanding (in millions)	540	549	544	550
Common equivalent shares:
Weighted-average common shares outstanding – assuming dilution (in millions)	545	556	549	556
Common Stock [Member]
Earnings per common share:
Net income attributable to Valero stockholders	$ 312	$ 674	$ 1,432	$ 1,073
Less dividends paid:
Common stock	121	96	340	261
Nonvested restricted stock	1	1	2	2
Undistributed earnings	190	577	1,090	810
Weighted-average common shares outstanding (in millions)	540	549	544	550
Earnings per common share:
Distributed earnings (in usd per share)	$ 0.23	$ 0.18	$ 0.63	$ 0.48
Undistributed earnings (in usd per share)	$ 0.35	$ 1.04	$ 1.99	$ 1.46
Total earnings per common share (in usd per share)	$ 0.58	$ 1.22	$ 2.62	$ 1.94
Earnings per common share – assuming dilution:
Net income attributable to Valero stockholders	$ 312	$ 674	$ 1,432	$ 1,073
Weighted-average common shares outstanding (in millions)	540	549	544	550
Common equivalent shares:
Stock options (in shares)	3	4	3	4
Performance awards and nonvested restricted stock (in shares)	2	3	2	2
Weighted-average common shares outstanding – assuming dilution (in millions)	545	556	549	556
Earnings per common share – assuming dilution (in usd per share)	$ 0.57	$ 1.21	$ 2.61	$ 1.93
Restricted Stock [Member]
Less dividends paid:
Weighted-average common shares outstanding (in millions)	3	3	3	3
Earnings per common share:
Distributed earnings (in usd per share)	$ 0.23	$ 0.18	$ 0.63	$ 0.48
Undistributed earnings (in usd per share)	$ 0.35	$ 1.04	$ 1.99	$ 1.46
Total earnings per common share (in usd per share)	$ 0.58	$ 1.22	$ 2.62	$ 1.94
Earnings per common share – assuming dilution:
Weighted-average common shares outstanding (in millions)	3	3	3	3

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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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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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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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