Debt, Credit Facilities (Details)		9 Months Ended	10 Months Ended	12 Months Ended
		Sep. 30, 2018 CAD ($)	Oct. 31, 2018	Dec. 31, 2018 CAD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 CAD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 CAD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 USD ($)
VLP Senior Notes Due in 2028 [Member] | Senior Notes [Member]
Credit Facilities (Textual)
Interest rate of notes (percent)				4.50%						4.50%
Valero Revolver [Member] | Credit Facilities [Member]
Line of Credit Facility
Facility amount										$ 3,000,000,000
Maturity date				Nov. 30, 2020	Nov. 30, 2020
Outstanding borrowings or letters of credit issued										0
Availability										2,943,000,000
Credit Facilities (Textual)
Borrowings from long-term lines of credit					$ 0		$ 0		$ 0
Repayments of long-term lines of credit					$ 0		0		0
Valero Revolver Letter of Credit [Member] | Credit Facilities [Member]
Line of Credit Facility
Facility amount										2,000,000,000
Outstanding borrowings or letters of credit issued										57,000,000
Canadian Revolver [Member] | Credit Facilities [Member]
Line of Credit Facility
Outstanding borrowings, short-term				$ 0
Canadian Revolver [Member] | Credit Facilities [Member]
Line of Credit Facility
Facility amount		$ 75,000,000		$ 150,000,000
Maturity date		Nov. 30, 2018		Nov. 30, 2019	Nov. 30, 2019
Availability				$ 145,000,000
Credit Facilities (Textual)
Borrowings from long-term lines of credit				0		$ 0		$ 0
Repayments of long-term lines of credit				0		$ 0		$ 0
Canadian Revolver Letter of Credit [Member] | Credit Facilities [Member]
Line of Credit Facility
Outstanding borrowings or letters of credit issued				$ 5,000,000
Committed Letter of Credit Facility Expires November 2019 [Member] | Credit Facilities [Member]
Line of Credit Facility
Facility amount										100,000,000
Maturity date			Nov. 30, 2018	Nov. 30, 2019	Nov. 30, 2019
Outstanding borrowings or letters of credit issued										0
Availability										100,000,000
Accounts Receivable Sales Facility [Member] | Credit Facilities [Member]
Line of Credit Facility
Outstanding borrowings, short-term										100,000,000
Accounts Receivable Sales Facility [Member] | Credit Facilities [Member]
Line of Credit Facility
Facility amount										1,300,000,000
Maturity date				Jul. 31, 2019	Jul. 31, 2019
Availability										$ 1,200,000,000
Credit Facilities (Textual)
Borrowings from long-term lines of credit					$ 0		$ 0		0
Interest rate of credit facility at period end (percent)				3.0618%			2.0387%			3.0618%
Repayments of long-term lines of credit					$ 0		$ 0		0
Designated pool of accounts receivable							2,300,000,000			$ 1,800,000,000
Uncommitted Letter of Credit Facility [Member]
Line of Credit Facility
Outstanding borrowings or letters of credit issued										229,000,000
Valero Energy Partners LP [Member] | VLP Senior Notes Due in 2028 [Member] | Senior Notes [Member]
Credit Facilities (Textual)
Face amount of long-term debt issuance										$ 500,000,000
Interest rate of notes (percent)				4.50%						4.50%
Valero Energy Partners LP [Member] | VLP Revolver [Member] | Credit Facilities [Member]
Line of Credit Facility
Facility amount							750,000,000			$ 750,000,000	[1],[2]
Maturity date	[1],[2]			Nov. 30, 2020	Nov. 30, 2020
Outstanding borrowings or letters of credit issued	[1],[2]									0
Availability	[1],[2]									750,000,000
Credit Facilities (Textual)
Borrowings from long-term lines of credit							$ 380,000,000		349,000,000
Interest rate of credit facility at period end (percent)							2.875%
Repayments of long-term lines of credit					$ 410,000,000		$ 0		$ 494,000,000
Valero Energy Partners LP [Member] | VLP Revolver Letter of Credit [Member] | Credit Facilities [Member]
Line of Credit Facility
Outstanding borrowings or letters of credit issued	[1],[2]									0
Central Mexico Terminals [Member] | IEnova Revolver [Member] | Credit Facilities [Member]
Line of Credit Facility
Facility amount	[1]									340,000,000
Maturity date	[1]			Feb. 28, 2028	Feb. 28, 2028
Outstanding borrowings	[1]									109,000,000
Availability	[1]									$ 231,000,000
Credit Facilities (Textual)
Interest rate of credit facility at period end (percent)				6.046%						6.046%
Amount borrowed					$ 109,000,000
Repayments of lines of credit					$ 0

[1] Creditors of our VIEs do not have recourse against us.

[2] The VLP Revolver was terminated on January 10, 2019. See “VLP Revolver” above.