Earnings (Loss) Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings (loss) per common share:
Net income (loss) attributable to Valero stockholders	$ 463	$ (464)	$ (79)	$ (1,062)
Less: Income allocated to participating securities	1	1	4	4
Net income (loss) available to common stockholders	$ 462	$ (465)	$ (83)	$ (1,066)
Weighted-average common shares outstanding (in shares)	407	407	407	407
Earnings (loss) per common share (in dollars per share)	$ 1.13	$ (1.14)	$ (0.20)	$ (2.62)
Earnings (loss) per common share – assuming dilution:
Net income (loss) attributable to Valero stockholders	$ 463	$ (464)	$ (79)	$ (1,062)
Less: Income allocated to participating securities	1	1	4	4
Net income (loss) available to common stockholders	$ 462	$ (465)	$ (83)	$ (1,066)
Weighted-average common shares outstanding (in shares)	407	407	407	407
Effect of dilutive securities (in shares)	1	0	0	0
Weighted-average common shares outstanding – assuming dilution (in shares)	408	407	407	407
Earnings (loss) per common share – assuming dilution (in dollars per share)	$ 1.13	$ (1.14)	$ (0.20)	$ (2.62)