Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Less dividends paid:
Weighted-average common shares outstanding (in shares)	469	513
Earnings per common share – assuming dilution:
Weighted-average common shares outstanding (in shares)	469	513
Common equivalent shares:
Weighted-average common shares outstanding – assuming dilution (in shares)	471	516
Common Class A [Member]
Earnings per common share:
Net income attributable to Valero stockholders	$ 495	$ 964
Less dividends paid:
Common stock	281	205
Participating securities	1	1
Undistributed earnings	$ 213	$ 758
Weighted-average common shares outstanding (in shares)	469	513
Earnings per common share:
Distributed earnings (in usd per share)	$ 0.60	$ 0.40
Undistributed earnings (in usd per share)	0.45	1.47
Total earnings per common share (in usd per share)	$ 1.05	$ 1.87
Earnings per common share – assuming dilution:
Net income attributable to Valero stockholders	$ 495	$ 964
Weighted-average common shares outstanding (in shares)	469	513
Common equivalent shares:
Stock options (in shares)	1	2
Performance awards and nonvested restricted stock (in shares)	1	1
Weighted-average common shares outstanding – assuming dilution (in shares)	471	516
Earnings per common share – assuming dilution (in usd per share)	$ 1.05	$ 1.87
Participating Securities [Member]
Less dividends paid:
Weighted-average common shares outstanding (in shares)	2	2
Earnings per common share:
Distributed earnings (in usd per share)	$ 0.60	$ 0.40
Undistributed earnings (in usd per share)	0.45	1.47
Total earnings per common share (in usd per share)	$ 1.05	$ 1.87
Earnings per common share – assuming dilution:
Weighted-average common shares outstanding (in shares)	2	2