Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net income	$ 1,457	$ 893
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	1,021	999
Deferred income tax expense (benefit)	(24)	24
Changes in current assets and current liabilities	(445)	859
Changes in deferred charges and credits and other operating activities, net	188	10
Net cash provided by operating activities	2,197	2,785
Cash flows from investing activities:
Capital expenditures	(740)	(572)
Deferred turnaround and catalyst costs	(490)	(308)
Investments in joint ventures	(119)	(222)
Peru Acquisition, net of cash acquired	(471)	0
Capital expenditures of certain variable interest entities	(78)	0
Acquisitions of undivided interests	(145)	(72)
Minor acquisitions	(91)	0
Other investing activities, net	2	0
Net cash used in investing activities	(2,132)	(1,174)
Cash flows from financing activities:
Proceeds from debt issuances and borrowings	1,314	0
Repayments of debt and capital lease obligations	(1,345)	(11)
Purchase of common stock for treasury	(647)	(660)
Common stock dividends	(690)	(627)
Proceeds from issuance of Valero Energy Partners LP common units	0	36
Contribution from noncontrolling interest	32	0
Distributions to noncontrolling interests	(50)	(45)
Other financing activities, net	(16)	(21)
Net cash used in financing activities	(1,402)	(1,328)
Effect of foreign exchange rate changes on cash	(62)	108
Net increase (decrease) in cash and cash equivalents	(1,399)	391
Cash and cash equivalents at beginning of period	5,850	4,816
Cash and cash equivalents at end of period	$ 4,451	$ 5,207