Revenues and Segment Information, Components of Operating Income (Details) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019 USD ($) refinery ethanol_plant	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) refinery ethanol_plant segment	Jun. 30, 2018 USD ($)
Segment Information for our Reportable Segments
Revenues	[1]	$ 28,933	$ 31,015	$ 53,196	$ 57,454
Cost of materials and other		26,083	27,860	48,061	51,616
Operating expenses (excluding depreciation and amortization expense reflected below)		1,175	1,110	2,390	2,246
Depreciation and amortization expense		552	510	1,089	995
Total cost of sales		27,810	29,480	51,540	54,857
Other operating expenses		2	21	4	31
General and administrative expenses (excluding depreciation and amortization expense reflected below)		199	248	408	486
Depreciation and amortization expense		14	13	28	26
Operating income (loss)		$ 908	1,253	$ 1,216	2,054
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		14		14
Corporate, Reconciling Items And Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		$ (133)	(98)	$ (238)	(189)
Operating income (loss)		(213)	(260)	(436)	(510)
Corporate [Member]
Segment Information for our Reportable Segments
Revenues		1	1	1	2
General and administrative expenses (excluding depreciation and amortization expense reflected below)		199	248	408	486
Depreciation and amortization expense		14	13	28	26
Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		(134)	(99)	(239)	(191)
Cost of materials and other		(133)	(99)	(238)	(191)
Operating expenses (excluding depreciation and amortization expense reflected below)		0	0	0	0
Depreciation and amortization expense		0	0	0	0
Total cost of sales		(133)	(99)	(238)	(191)
Other operating expenses		0	0	0	0
Refining [Member]
Segment Information for our Reportable Segments
Revenues		27,746	30,024	50,964	55,477
Refining [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues		27,754	30,035	50,974	55,492
Cost of materials and other		25,172	27,103	46,337	50,267
Operating expenses (excluding depreciation and amortization expense reflected below)		1,026	988	2,097	1,999
Depreciation and amortization expense		518	483	1,021	944
Total cost of sales		26,716	28,574	49,455	53,210
Other operating expenses		1	21	3	31
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 (loss)		1,037	1,440	1,516	2,251
Refining [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		8	11	10	15
Ethanol [Member]
Segment Information for our Reportable Segments
Revenues		964	884	1,757	1,761
Ethanol [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues		1,017	926	1,862	1,849
Cost of materials and other		855	754	1,549	1,503
Operating expenses (excluding depreciation and amortization expense reflected below)		132	109	257	220
Depreciation and amortization expense		22	20	45	38
Total cost of sales		1,009	883	1,851	1,761
Other operating expenses		1	0	1	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 (loss)		7	43	10	88
Ethanol [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		53	42	105	88
Renewable Diesel [Member]
Segment Information for our Reportable Segments
Revenues		222	106	474	214
Renewable Diesel [Member] | Operating Segments [Member]
Segment Information for our Reportable Segments
Revenues		295	152	598	302
Cost of materials and other		189	102	413	37
Operating expenses (excluding depreciation and amortization expense reflected below)		17	13	36	27
Depreciation and amortization expense		12	7	23	13
Total cost of sales		218	122	472	77
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 (loss)		77	30	126	225
Renewable Diesel [Member] | Intersegment Eliminations [Member]
Segment Information for our Reportable Segments
Revenues		$ 73	$ 46	$ 124	$ 88

[1] Includes excise taxes on sales by certain of our international operations of $1,410 million and $1,470 million for the three months ended June 30, 2019 and 2018, respectively, and $2,740 million and $2,934 million for the six months ended June 30, 2019 and 2018, respectively.