Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Less dividends paid:
Weighted-average common shares outstanding (in shares)	458	491	465	503
Earnings per common share – assuming dilution:
Weighted-average common shares outstanding (in shares)	458	491	465	503
Common equivalent shares:
Weighted-average common shares outstanding – assuming dilution (in shares)	460	494	467	506
Common Class A [Member]
Earnings per common share:
Net income attributable to Valero stockholders	$ 613	$ 1,377	$ 1,922	$ 3,692
Less dividends paid:
Common stock	275	198	837	606
Participating securities	1	1	3	2
Undistributed earnings	$ 337	$ 1,178	$ 1,082	$ 3,084
Weighted-average common shares outstanding (in shares)	458	491	465	503
Earnings per common share:
Distributed earnings (in usd per share)	$ 0.60	$ 0.40	$ 1.80	$ 1.20
Undistributed earnings (in usd per share)	0.73	2.39	2.32	6.11
Total earnings per common share (in usd per share)	$ 1.33	$ 2.79	$ 4.12	$ 7.31
Earnings per common share – assuming dilution:
Net income attributable to Valero stockholders	$ 613	$ 1,377	$ 1,922	$ 3,692
Weighted-average common shares outstanding (in shares)	458	491	465	503
Common equivalent shares:
Stock options (in shares)	1	1	1	2
Performance awards and nonvested restricted stock (in shares)	1	2	1	1
Weighted-average common shares outstanding – assuming dilution (in shares)	460	494	467	506
Earnings per common share – assuming dilution (in usd per share)	$ 1.33	$ 2.79	$ 4.12	$ 7.30
Participating Securities [Member]
Less dividends paid:
Weighted-average common shares outstanding (in shares)	1	2	1	2
Earnings per common share:
Distributed earnings (in usd per share)	$ 0.60	$ 0.40	$ 1.80	$ 1.20
Undistributed earnings (in usd per share)	0.73	2.39	2.32	6.11
Total earnings per common share (in usd per share)	$ 1.33	$ 2.79	$ 4.12	$ 7.31
Earnings per common share – assuming dilution:
Weighted-average common shares outstanding (in shares)	1	2	1	2