Revenues and Segment Information, Revenue by Product (Details) - USD ($) $ in Millions	3 Months Ended									12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	[1]	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Revenue from External Customer [Line Items]
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]
Corporate [Member]
Revenue from External Customer [Line Items]
Revenues										4		5		0
Intersegment Eliminations [Member]
Revenue from External Customer [Line Items]
Revenues										(770)		(634)		(573)
Other Revenues [Member] | Corporate [Member]
Revenue from External Customer [Line Items]
Revenues										4		5		0
Refining [Member]
Revenue from External Customer [Line Items]
Revenues										113,601		90,651		71,968
Refining [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										113,615		90,657		71,968
Refining [Member] | Intersegment Eliminations [Member]
Revenue from External Customer [Line Items]
Revenues										14		6		0
Refining [Member] | Gasoline and Blendstocks [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										46,606		40,366		33,450
Refining [Member] | Distillates [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										55,546		42,074		32,576
Refining [Member] | Other Product Revenues [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										11,463		8,217		5,942
Ethanol [Member]
Revenue from External Customer [Line Items]
Revenues										3,428		3,324		3,691
Ethanol [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										3,638		3,500		3,901
Ethanol [Member] | Intersegment Eliminations [Member]
Revenue from External Customer [Line Items]
Revenues										210		176		210
Ethanol [Member] | Ethanol [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										2,912		2,940		3,315
Ethanol [Member] | Distillers Grains [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										726		560		586
VLP [Member]
Revenue from External Customer [Line Items]
Revenues										0		0		0
VLP [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										546		452		363
VLP [Member] | Intersegment Eliminations [Member]
Revenue from External Customer [Line Items]
Revenues										546		452		363
VLP [Member] | Pipeline Transportation [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										124		101		78
VLP [Member] | Terminaling [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										415		348		284
VLP [Member] | Storage and Other [Member] | Operating Segments [Member]
Revenue from External Customer [Line Items]
Revenues										$ 7		$ 3		$ 1

[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.