Employee Benefit Plans (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Changes in plan assets(a):
Fair value of plan assets at beginning of year		$ 1,947
Fair value of plan assets at end of year		2,097		$ 1,947
Defined Benefit Plan, Amounts Recognized in Balance Sheet
Accrued expenses		(32)		(40)
Other long-term liabilities		(742)		(719)
Employee Benefit Plans (Textual)
Contributions to defined contribution plans		67		65		$ 61
Pension Plans [Member]
Changes in benefit obligation:
Benefit obligation at beginning of year		2,365	[1]	2,450
Service cost		111		109		120
Interest cost		84		98		91
Participant contributions	[1]	0		0
Plan amendments		0		22
Benefits paid	[1]	(130)		(169)
Actuarial (gain) loss		171		(138)
Other		(34)		(7)
Benefit obligation at end of year		2,567	[1]	2,365	[1]	2,450
Changes in plan assets(a):
Fair value of plan assets at beginning of year	[1]	1,947		1,978
Actual return on plan assets	[1]	165		19
Valero contributions	[1]	141		126
Participant contributions	[1]	0		0
Benefits paid	[1]	(130)		(169)
Other	[1]	(26)		(7)
Fair value of plan assets at end of year	[1]	2,097		1,947		1,978
Reconciliation of funded status (a):
Funded status as of end of year	[1]	(470)		(418)
Accumulated benefit obligation		2,419		2,240
Defined Benefit Plan, Amounts Recognized in Balance Sheet
Deferred charges and other assets, net		2		5
Accrued expenses		(13)		(20)
Other long-term liabilities		(459)		(403)
Amounts recognized in balance sheet for defined benefit plans		(470)		(418)
Other Postretirement Benefit Plans [Member]
Changes in benefit obligation:
Benefit obligation at beginning of year		336	[1]	361
Service cost		7		8		7
Interest cost		12		14		15
Participant contributions	[1]	8		8
Plan amendments		0		0
Benefits paid	[1]	(27)		(27)
Actuarial (gain) loss		(35)		(26)
Other		1		(2)
Benefit obligation at end of year		302	[1]	336	[1]	361
Changes in plan assets(a):
Fair value of plan assets at beginning of year	[1]	0		0
Actual return on plan assets	[1]	0		0
Valero contributions	[1]	18		18
Participant contributions	[1]	8		8
Benefits paid	[1]	(27)		(27)
Other	[1]	1		1
Fair value of plan assets at end of year	[1]	0		0		$ 0
Reconciliation of funded status (a):
Funded status as of end of year	[1]	(302)		(336)
Defined Benefit Plan, Amounts Recognized in Balance Sheet
Deferred charges and other assets, net		0		0
Accrued expenses		(19)		(20)
Other long-term liabilities		(283)		(316)
Amounts recognized in balance sheet for defined benefit plans		$ (302)		$ (336)

[1] Plan assets include only the assets associated with pension plans subject to legal minimum funding standards. Plan assets associated with U.S. nonqualified pension plans are not included here because they are not protected from our creditors and therefore cannot be reflected as a reduction from our obligations under the pension plans. As a result, the reconciliation of funded status does not reflect the effect of plan assets that exist for all of our defined benefit plans. See Note 18 for the assets associated with certain U.S. nonqualified pension plans.