Revenues and Segment Information, Components of Operating Income (Details) $ in Millions		3 Months Ended
		Mar. 31, 2018 USD ($) refinery ethanol_plant segment	Mar. 31, 2017 USD ($)
Segment Information for our Reportable Segments
Revenues	[1]	$ 26,439	$ 21,772
Cost of materials and other		23,756	19,428
Operating expenses (excluding depreciation and amortization expense reflected below)		1,136	1,124
Depreciation and amortization expense		485	488
Total cost of sales		25,377	21,040
Other operating expenses		10	0
General and administrative expenses (excluding depreciation and amortization expense reflected below)		238	192
Depreciation and amortization expense		13	12
Operating income		$ 801	528
Disclosure of Entity's Reportable Segments (Textual)
Number of reportable segments | segment		3
Number of petroleum refineries | refinery		15
Number of ethanol plants | ethanol_plant		11
Corporate, Reconciling Items And Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		$ (181)	(166)
Operating income		(250)	(204)
Corporate [Member]
Segment Information for our Reportable Segments
Revenues		1	0
General and administrative expenses (excluding depreciation and amortization expense reflected below)		238	192
Depreciation and amortization expense		13	12
Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		(182)	(166)
Cost of materials and other		(181)	(166)
Operating expenses (excluding depreciation and amortization expense reflected below)		(1)	0
Depreciation and amortization expense		0	0
Total cost of sales		(182)	(166)
Other operating expenses		0
Refining [Member]
Segment Information for our Reportable Segments
Revenues		25,561	20,887
Refining [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues		25,565	20,887
Cost of materials and other		23,188	18,807
Operating expenses (excluding depreciation and amortization expense reflected below)		997	991
Depreciation and amortization expense		448	449
Total cost of sales		24,633	20,247
Other operating expenses		10
General and administrative expenses (excluding depreciation and amortization expense reflected below)		0	0
Depreciation and amortization expense		0	0
Operating income		922	640
Refining [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		4	0
Ethanol [Member]
Segment Information for our Reportable Segments
Revenues		877	885
Ethanol [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues		923	945
Cost of materials and other		749	787
Operating expenses (excluding depreciation and amortization expense reflected below)		111	109
Depreciation and amortization expense		18	27
Total cost of sales		878	923
Other operating expenses		0
General and administrative expenses (excluding depreciation and amortization expense reflected below)		0	0
Depreciation and amortization expense		0	0
Operating income		45	22
Ethanol [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		46	60
VLP [Member]
Segment Information for our Reportable Segments
Revenues		0	0
VLP [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues		132	106
Cost of materials and other		0	0
Operating expenses (excluding depreciation and amortization expense reflected below)		29	24
Depreciation and amortization expense		19	12
Total cost of sales		48	36
Other operating expenses		0
General and administrative expenses (excluding depreciation and amortization expense reflected below)		0	0
Depreciation and amortization expense		0	0
Operating income		84	70
VLP [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		$ 132	$ 106

[1] Includes excise taxes on sales by certain of our international operations of $1,464 million and $1,272 million for the three months ended March 31, 2018 and 2017, respectively.