Variable Interest Entities (Consolidated VIEs) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 1,091	$ 1,527
Receivables, less allowance for doubtful accounts	4,361	7,479
Inventories	8,086	10,243
Other current assets	1,105	921
Equity method investments	5,740	6,898
Property, plant and equipment, net	45,025	45,615
Goodwill	12,710	20,040
Right of use assets	2,454	2,459
Other noncurrent assets	4,021	3,374
Liabilities
Accounts payable	6,110	11,623
Payroll and benefits payable	815	1,126
Accrued taxes	1,272	1,186
Debt due within one year	1,715	711
Operating lease liabilities	625	604
Other current liabilities	967	897
Long-term debt	30,451	28,127
Deferred income taxes	5,914	6,392
Long-term operating lease liabilities	1,850	1,875
Deferred credits and other liabilities	1,285	1,265
Variable Interest Entity, Primary Beneficiary [Member] | MPLX
Assets
Cash and cash equivalents	67	15
Receivables, less allowance for doubtful accounts	567	615
Inventories	115	110
Other current assets	49	110
Equity method investments	4,065	5,275
Property, plant and equipment, net	21,958	22,174
Goodwill	7,722	9,536
Right of use assets	341	365
Other noncurrent assets	1,074	1,323
Liabilities
Accounts payable	471	744
Payroll and benefits payable	2	5
Accrued taxes	83	80
Debt due within one year	3	9
Operating lease liabilities	69	66
Other current liabilities	265	259
Long-term debt	20,556	19,704
Deferred income taxes	11	12
Long-term operating lease liabilities	274	302
Deferred credits and other liabilities	$ 442	$ 409