Earnings Per Common Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended											12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012		Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Earnings per common share from continuing operations:
Net income attributable to Valero stockholders from continuing operations												$ 2,083	$ 2,097	$ 923
Less dividends paid:
Weighted-average common shares outstanding												550	563	563
Earnings per common share from continuing operations:
Distributed earnings												$ 0.65	$ 0.30	$ 0.20
Total earnings per common share from continuing operations												$ 3.77	$ 3.70	$ 1.63
Earnings per common share from continuing operations – assuming dilution:
Net income attributable to Valero stockholders from continuing operations												2,083	2,097	923
Weighted-average common shares outstanding												550	563	563
Common equivalent shares:
Weighted-average common shares outstanding – assuming dilution												556	569	568
Earnings per common share from continuing operations – assuming dilution	$ 1.82	$ 1.21	$ 1.50	$ (0.78)	[1]	$ 0.08	[2]	$ 2.11	[3]	$ 1.30	$ 0.18	$ 3.75	$ 3.69	$ 1.62
Restricted Stock [Member]
Less dividends paid:
Weighted-average common shares outstanding												3	3	3
Earnings per common share from continuing operations:
Distributed earnings												$ 0.65	$ 0.30	$ 0.20
Undistributed earnings												$ 3.12	$ 3.40	$ 1.43
Total earnings per common share from continuing operations												$ 3.77	$ 3.70	$ 1.63
Earnings per common share from continuing operations – assuming dilution:
Weighted-average common shares outstanding												3	3	3
Common Stock [Member]
Earnings per common share from continuing operations:
Net income attributable to Valero stockholders from continuing operations												2,083	2,097	923
Less dividends paid:
Common stock												358	168	113
Nonvested restricted stock												2	1	1
Undistributed earnings												1,723	1,928	809
Weighted-average common shares outstanding												550	563	563
Earnings per common share from continuing operations:
Distributed earnings												$ 0.65	$ 0.30	$ 0.20
Undistributed earnings												$ 3.12	$ 3.40	$ 1.43
Total earnings per common share from continuing operations												$ 3.77	$ 3.70	$ 1.63
Earnings per common share from continuing operations – assuming dilution:
Net income attributable to Valero stockholders from continuing operations												$ 2,083	$ 2,097	$ 923
Weighted-average common shares outstanding												550	563	563
Common equivalent shares:
Stock options												4	4	3
Performance awards and unvested restricted stock												2	2	2
Weighted-average common shares outstanding – assuming dilution												556	569	568
Earnings per common share from continuing operations – assuming dilution												$ 3.75	$ 3.69	$ 1.62

[1] The operations of the Aruba Refinery were suspended in March 2012.

[2] Includes the operations related to the Meraux Acquisition beginning October 1, 2011.

[3] Includes the operations related to the Pembroke Acquisition beginning August 1, 2011.