Quarterly Financial Data (Unaudited) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended									12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013		Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Results of operations
Operating revenues	$ 27,859	$ 34,408	$ 34,914	$ 33,663	$ 34,429	$ 36,137	$ 34,034	[1]	$ 33,474	$ 130,844	$ 138,074	$ 138,393
Operating income	1,796	1,670	1,085	1,351	1,562	532	805	[1]	1,058	5,902	3,957	5,044
Net income	1,220	1,062	593	836	1,287	324	465	[1]	652	3,711	2,728	2,080
Net income attributable to Valero Energy Corporation stockholders	$ 1,155	$ 1,059	$ 588	$ 828	$ 1,288	$ 312	$ 466	[1]	$ 654	$ 3,630	$ 2,720	$ 2,083
Earnings per common share (in usd per share)	$ 2.22	$ 2.01	$ 1.11	$ 1.55	$ 2.39	$ 0.58	$ 0.86	[1]	$ 1.18	$ 6.88	$ 4.99	$ 3.77
Earnings per common share - assuming dilution (in usd per share)	$ 2.22	$ 2.00	$ 1.10	$ 1.54	$ 2.38	$ 0.57	$ 0.85	[1]	$ 1.18	$ 6.85	$ 4.97	$ 3.75

[1] The separation of our retail business was completed on May 1, 2013.