Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities:
Net income	$ 2,728	$ 2,080	$ 2,089
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	1,720	1,574	1,534
Gain on disposition of retained interest in CST Brands, Inc.	(325)	0	0
Asset impairment losses	0	1,014	0
Loss on sales of refinery assets, net	0	0	12
Stock-based compensation expense	64	58	58
Deferred income tax expense	501	963	461
Changes in current assets and current liabilities	922	(302)	81
Changes in deferred charges and credits and other operating activities, net	(46)	(117)	(197)
Net cash provided by operating activities	5,564	5,270	4,038
Cash flows from investing activities:
Capital expenditures	(2,121)	(2,931)	(2,355)
Deferred turnaround and catalyst costs	(634)	(479)	(629)
Acquisition of Pembroke Refinery, net of cash acquired	0	0	(1,691)
Acquisition of Meraux Refinery	0	0	(547)
Proceeds from the sale of the Paulsboro Refinery	0	160	0
Other investing activities, net	(57)	(101)	(76)
Net cash used in investing activities	(2,812)	(3,351)	(5,298)
Cash flows from financing activities:
Proceeds from debt borrowings	0	2,900	150
Repayments of debt	(480)	(3,612)	(778)
Proceeds from the exercise of stock options	59	59	49
Purchase of common stock for treasury	(928)	(281)	(349)
Common stock dividends	(462)	(360)	(169)
Net proceeds from initial public offering of common units of Valero Energy Partners LP	369	0	0
Contributions from noncontrolling interests	45	44	22
Disposition of retail business:
Proceeds from short-term debt in anticipation of separation	550	0	0
Cash distributed to Valero by CST Brands, Inc.	500	0	0
Cash held and retained by CST Brands, Inc. upon separation	(315)	0	0
Proceeds from short-term debt related to disposition of retained interest	525	0	0
Repayments of short-term debt related to disposition of retained interest	(58)	0	0
Other financing activities, net	32	17	9
Net cash used in financing activities	(163)	(1,233)	(1,066)
Effect of foreign exchange rate changes on cash	(20)	13	16
Net increase (decrease) in cash and temporary cash investments	2,569	699	(2,310)
Cash and temporary cash investments at beginning of year	1,723	1,024	3,334
Cash and temporary cash investments at end of year	$ 4,292	$ 1,723	$ 1,024