Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues and other income:
Sales and other operating revenues, excluding consumer excise taxes	[1],[2]	$ 95,750
Sales and other operating revenue, including excise taxes	[2]		$ 74,104	$ 63,277
Sales to related parties	[3]	754	629	62
Income (loss) from equity method investments		373	306	(185)
Net gain on disposal of assets		23	10	32
Other income		202	320	178
Total revenues and other income		97,102	75,369	63,364
Costs and expenses:
Cost of revenues (excludes items below)	[2]	85,456	66,519	56,676
Purchases from related parties	[4]	610	570	509
Inventory market valuation adjustment		0	0	(370)
Impairment expense		0	0	130
Depreciation and amortization		2,490	2,114	2,001
Selling, general and administrative expenses		2,418	1,694	1,597
Other taxes		557	454	435
Total costs and expenses		91,531	71,351	60,978
Income from operations		5,571	4,018	2,386
Net interest and other financial costs		1,003	674	564
Income before income taxes		4,568	3,344	1,822
(Benefit) provision for income taxes		962	(460)	609
Net income		3,606	3,804	1,213
Less net income (loss) attributable to:
Redeemable noncontrolling interest		75	65	41
Noncontrolling interests		751	307	(2)
Net income attributable to MPC		$ 2,780	$ 3,432	$ 1,174
Basic:
Net income attributable to MPC per share		$ 5.36	$ 6.76	$ 2.22
Weighted average shares outstanding (in shares)		518	507	528
Diluted:
Net income attributable to MPC per share		$ 5.28	$ 6.70	$ 2.21
Weighted average shares outstanding (in shares)		526	512	530

[1] The 2018 period reflects an election to present certain taxes on a net basis concurrent with our adoption of ASC 606.

[2] The 2018 period reflects an election to present certain taxes on a net basis concurrent with our adoption of ASU 2014-09, Revenue - Revenue from Contracts with Customers (“ASC 606”). See Notes 2 and 3 for further information.

[3] Sales to related parties consists primarily of sales of refined products to PFJ Southeast, an equity affiliate which owns and operates travel plazas primarily in the Southeast region of the United States.

[4] We obtain transportation services and purchase ethanol from certain of our equity affiliates, none of which is individually material.