Consolidated Statements of Cash Flows (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities:
Net income	$ 836	$ 652
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	421	430
Deferred income tax expense	88	173
Changes in current assets and current liabilities	(1,088)	255
Changes in deferred charges and credits and other operating activities, net	(13)	39
Net cash provided by operating activities	244	1,549
Cash flows from investing activities:
Capital expenditures	(388)	(577)
Deferred turnaround and catalyst costs	(129)	(287)
Other investing activities, net	(41)	4
Net cash used in investing activities	(558)	(860)
Cash flows from financing activities:
Repayment of debt	0	(180)
Proceeds from the exercise of stock options	24	38
Purchase of common stock for treasury	(226)	(304)
Common stock dividends	(133)	(111)
Contributions from noncontrolling interests	0	13
Distributions to public unitholders of Valero Energy Partners LP	(1)	0
Other financing activities, net	24	22
Net cash used in financing activities	(312)	(522)
Effect of foreign exchange rate changes on cash	(19)	(33)
Net increase (decrease) in cash and temporary cash investments	(645)	134
Cash and temporary cash investments at beginning of period	4,292	1,723
Cash and temporary cash investments at end of period	$ 3,647	$ 1,857