Earnings (Loss) Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings (loss) per common share
Net income (loss) attributable to Valero stockholders	$ (1,851)	$ 141
Less: Income allocated to participating securities	1	1
Net income (loss) available to common stockholders	$ (1,852)	$ 140
Weighted-average common shares outstanding (in shares)	408	416
Earnings (loss) per common share (in dollars per share)	$ (4.54)	$ 0.34
Earnings (loss) per common share – assuming dilution
Net income (loss) attributable to Valero stockholders	$ (1,851)	$ 141
Weighted-average common shares outstanding (in shares)	408	416
Effect of dilutive securities (in shares)	0	2
Weighted-average common shares outstanding – assuming dilution (in shares)	408	418
Earnings (loss) per common share – assuming dilution (in dollars per share)	$ (4.54)	$ 0.34