Revenues and Segment Information, Components of Operating Income (Details) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2018 USD ($) refinery ethanol_plant	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) refinery ethanol_plant segment	Sep. 30, 2017 USD ($)
Segment Information for our Reportable Segments
Revenues	[1]	$ 30,849	$ 23,562	$ 88,303	$ 67,588
Cost of materials and other		27,701	20,329	79,317	59,366
Operating expenses (excluding depreciation and amortization expense reflected below)		1,193	1,135	3,439	3,370
Depreciation and amortization expense		504	484	1,499	1,457
Total cost of sales		29,398	21,948	84,255	64,193
Other operating expenses		10	44	41	44
General and administrative expenses (excluding depreciation and amortization expense reflected below)		209	225	695	592
Depreciation and amortization expense		13	13	39	39
Operating income		$ 1,219	1,332	$ 3,273	2,720
Disclosure of Entity's Reportable Segments (Textual)
Number of reportable segments | segment				3
Number of petroleum refineries | refinery		15		15
Number of ethanol plants | ethanol_plant		11		11
Corporate, Reconciling Items And Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		$ (212)	(159)	$ (570)	(463)
Operating income		(221)	(238)	(731)	(631)
Corporate [Member]
Segment Information for our Reportable Segments
Revenues		1	0	3	0
General and administrative expenses (excluding depreciation and amortization expense reflected below)		209	225	695	592
Depreciation and amortization expense		13	13	39	39
Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		(213)	(159)	(573)	(463)
Cost of materials and other		(212)	(158)	(570)	(462)
Operating expenses (excluding depreciation and amortization expense reflected below)		(1)	(1)	(3)	(1)
Depreciation and amortization expense		0	0	0	0
Total cost of sales		(213)	(159)	(573)	(463)
Other operating expenses		0	0	0	0
Refining [Member]
Segment Information for our Reportable Segments
Revenues		29,984	22,728	85,675	65,030
Refining [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues		29,989	22,729	85,685	65,031
Cost of materials and other		27,137	19,818	77,608	57,662
Operating expenses (excluding depreciation and amortization expense reflected below)		1,047	996	3,013	2,966
Depreciation and amortization expense		466	455	1,385	1,358
Total cost of sales		28,650	21,269	82,006	61,986
Other operating expenses		10	41	41	41
General and administrative expenses (excluding depreciation and amortization expense reflected below)		0	0	0	0
Depreciation and amortization expense		0	0	0	0
Operating income		1,329	1,419	3,638	3,004
Refining [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		5	1	10	1
Ethanol [Member]
Segment Information for our Reportable Segments
Revenues		864	834	2,625	2,558
Ethanol [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues		932	882	2,781	2,694
Cost of materials and other		776	669	2,279	2,166
Operating expenses (excluding depreciation and amortization expense reflected below)		116	114	336	330
Depreciation and amortization expense		19	17	57	63
Total cost of sales		911	800	2,672	2,559
Other operating expenses		0	0	0	0
General and administrative expenses (excluding depreciation and amortization expense reflected below)		0	0	0	0
Depreciation and amortization expense		0	0	0	0
Operating income		21	82	109	135
Ethanol [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		68	48	156	136
VLP [Member]
Segment Information for our Reportable Segments
Revenues		0	0	0	0
VLP [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues		140	110	407	326
Cost of materials and other		0	0	0	0
Operating expenses (excluding depreciation and amortization expense reflected below)		31	26	93	75
Depreciation and amortization expense		19	12	57	36
Total cost of sales		50	38	150	111
Other operating expenses		0	3	0	3
General and administrative expenses (excluding depreciation and amortization expense reflected below)		0	0	0	0
Depreciation and amortization expense		0	0	0	0
Operating income		90	69	257	212
VLP [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		$ 140	$ 110	$ 407	$ 326

[1] Includes excise taxes on sales by certain of our international operations of $1,338 million and $1,447 million for the three months ended September 30, 2018 and 2017, respectively, and $4,272 million and $4,103 million for the nine months ended September 30, 2018 and 2017, respectively.