Revenues and Segment Information, Activity (Details) $ in Millions		3 Months Ended									12 Months Ended
		Dec. 31, 2018 USD ($) refinery ethanol_plant	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	[1]	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) refinery ethanol_plant segment		Dec. 31, 2017 USD ($)		Dec. 31, 2016 USD ($)
Segment Information for our Reportable Segments
Revenues		$ 28,730	$ 30,849	$ 31,015	$ 26,439	$ 26,392		$ 23,562	$ 22,254	$ 21,772	$ 117,033	[2]	$ 93,980	[2]	$ 75,659	[2]
Cost of sales:
Cost of materials and other											104,732		83,037		65,962
Operating expenses (excluding depreciation and amortization expense reflected below)											4,690		4,504		4,251
Depreciation and amortization expense											2,017		1,934		1,846
Lower of cost or market inventory valuation adjustment											0		0		(747)
Total cost of sales											111,439		89,475		71,312
Other operating expenses											45		61		0
General and administrative expenses (excluding depreciation and amortization expense reflected below)											925		829		709
Depreciation and amortization expense											52		52		48
Asset impairment loss											0		0		56
Operating income by segment		$ 1,299	$ 1,219	$ 1,253	$ 801	$ 843		$ 1,332	$ 860	$ 528	4,572		3,563		3,534
Total expenditures for long-lived assets	[3]										$ 3,376		1,948		1,996
Segment Information (Textual)
Number of reportable segments | segment											3
Number of petroleum refineries | refinery		15									15
Number of ethanol plants | ethanol_plant		14									14
Corporate, Reconciling Items, and Eliminations[Member]
Segment Information for our Reportable Segments
Revenues											$ (766)		(629)		(573)
Cost of sales:
Operating income by segment											(974)		(876)		(757)
Corporate [Member]
Segment Information for our Reportable Segments
Revenues											4		5		0
Cost of sales:
General and administrative expenses (excluding depreciation and amortization expense reflected below)											925		829		709
Depreciation and amortization expense											52		52		48
Asset impairment loss															0
Total expenditures for long-lived assets	[3]										44		44		38
Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues											(770)		(634)		(573)
Cost of sales:
Cost of materials and other											(765)		(632)		(573)
Operating expenses (excluding depreciation and amortization expense reflected below)											(4)		(2)		0
Depreciation and amortization expense											0		0		0
Total cost of sales											(769)		(634)		(573)
Other operating expenses											0		0
Refining [Member]
Segment Information for our Reportable Segments
Revenues											113,601		90,651		71,968
Refining [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues											113,615		90,657		71,968
Cost of sales:
Cost of materials and other											102,489		80,865		63,405
Operating expenses (excluding depreciation and amortization expense reflected below)											4,099		3,959		3,740
Depreciation and amortization expense											1,863		1,800		1,734
Lower of cost or market inventory valuation adjustment															(697)
Total cost of sales											108,451		86,624		68,182
Other operating expenses											45		58
General and administrative expenses (excluding depreciation and amortization expense reflected below)											0		0		0
Depreciation and amortization expense											0		0		0
Asset impairment loss															56
Operating income by segment											5,119		3,975		3,730
Total expenditures for long-lived assets	[3]										2,935		1,710		1,867
Refining [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues											14		6		0
Ethanol [Member]
Segment Information for our Reportable Segments
Revenues											3,428		3,324		3,691
Ethanol [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues											3,638		3,500		3,901
Cost of sales:
Cost of materials and other											3,008		2,804		3,130
Operating expenses (excluding depreciation and amortization expense reflected below)											470		443		415
Depreciation and amortization expense											78		81		66
Lower of cost or market inventory valuation adjustment															(50)
Total cost of sales											3,556		3,328		3,561
Other operating expenses											0		0
General and administrative expenses (excluding depreciation and amortization expense reflected below)											0		0		0
Depreciation and amortization expense											0		0		0
Asset impairment loss															0
Operating income by segment											82		172		340
Total expenditures for long-lived assets	[3]										373		84		68
Ethanol [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues											210		176		210
VLP [Member]
Segment Information for our Reportable Segments
Revenues											0		0		0
VLP [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues											546		452		363
Cost of sales:
Cost of materials and other											0		0		0
Operating expenses (excluding depreciation and amortization expense reflected below)											125		104		96
Depreciation and amortization expense											76		53		46
Lower of cost or market inventory valuation adjustment															0
Total cost of sales											201		157		142
Other operating expenses											0		3
General and administrative expenses (excluding depreciation and amortization expense reflected below)											0		0		0
Depreciation and amortization expense											0		0		0
Asset impairment loss															0
Operating income by segment											345		292		221
Total expenditures for long-lived assets	[3]										24		110		23
VLP [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues											$ 546		$ 452		$ 363

[1] During the quarter ended December 31, 2017, we recognized an income tax benefit of $1.9 billion related to Tax Reform as described in Note 15.

[2] Includes excise taxes on sales by certain of our international operations of $5,626 million, $5,573 million, and $5,493 million for the years ended December 31, 2018, 2017, and 2016.

[3] Total expenditures for long-lived assets includes amounts related to capital expenditures, deferred turnaround and catalyst costs, and property, plant, and equipment for acquisitions.