Consolidated Statements of Cash Flows (Unaudited) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities:
Net income	$ 1,429	$ 1,117
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	835	835
Aruba Refinery asset retirement expense and other	63	0
Deferred income tax expense	73	341
Changes in current assets and current liabilities	(1,024)	444
Changes in deferred charges and credits and other operating activities, net	2	77
Net cash provided by operating activities	1,378	2,814
Cash flows from investing activities:
Capital expenditures	(954)	(1,211)
Deferred turnaround and catalyst costs	(369)	(449)
Other investing activities, net	(43)	(23)
Net cash used in investing activities	(1,366)	(1,683)
Cash flows from financing activities:
Repayment of debt	(200)	(480)
Proceeds from the exercise of stock options	32	43
Purchase of common stock for treasury	(455)	(560)
Common stock dividends	(266)	(220)
Contributions from noncontrolling interests	14	45
Distributions to public unitholders of Valero Energy Partners LP	(4)	0
Disposition of retail business:
Proceeds from short-term debt in anticipation of separation	0	550
Cash distributed to Valero by CST Brands, Inc.	0	500
Cash held and retained by CST Brands, Inc. upon separation	0	(315)
Other financing activities, net	52	24
Net cash used in financing activities	(827)	(413)
Effect of foreign exchange rate changes on cash	3	(43)
Net increase (decrease) in cash and temporary cash investments	(812)	675
Cash and temporary cash investments at beginning of period	4,292	1,723
Cash and temporary cash investments at end of period	$ 3,480	$ 2,398