Supplemental Cash Flow Information (Details) - USD ($) $ in Millions			9 Months Ended
		Jan. 01, 2019	Sep. 30, 2020	Sep. 30, 2019
Decrease (increase) in current assets:
Receivables, net			$ 3,229	$ (241)
Inventories			1,577	126
Prepaid expenses and other			70	(55)
Increase (decrease) in current liabilities:
Accounts payable			(4,893)	914
Accrued expenses			17	(92)
Taxes other than income taxes payable			(24)	(25)
Income taxes payable			(208)	101
Changes in current assets and current liabilities			(232)	728
Cash Flows Related to Interest and Income Taxes
Interest paid in excess of amount capitalized, including interest on finance leases			338	303
Income taxes paid (refunded), net			206	(184)
Operating cash flows
Operating Leases			329	329
Finance Leases			74	38
Investing cash flows
Operating Leases			1	1
Financing cash flows
Finance Leases			51	31
Changes in lease balances resulting from new and modified leases, Operating Leases	[1]		211	1,673
Changes in lease balances resulting from new and modified leases, Finance Leases	[1]		1,506	221
Supplemental Cash Flow Information (Textual)
Decrease in receivables as a result of decreases in sales volumes and commodity prices			3,600
Increase in income taxes receivable			770
Topic 842 [Member]
Financing cash flows
Changes in lease balances resulting from new and modified leases, Operating Leases		$ 1,300
MVP Terminal [Member]
Financing cash flows
Changes in lease balances resulting from new and modified leases, Finance Leases			1,400
Internal Revenue Service (IRS) [Member] | Domestic Tax Authority [Member]
Supplemental Cash Flow Information (Textual)
Refund received, including interest, associated with income tax settlement				$ 348
Blender's Tax Credit Receivable [Member]
Supplemental Cash Flow Information (Textual)
Collection of blender's tax credit receivable			$ 449

[1] Noncash activity for the nine months ended September 30, 2020 primarily includes $1.4 billion for a finance lease ROU asset and related liability recognized in connection with the terminaling agreement with MVP described in Note 5. Noncash activity for the nine months ended September 30, 2019 included $1.3 billion for operating lease ROU assets and related liabilities recorded on January 1, 2019 upon adoption of Financial Accounting Standards Board Accounting Standards Codification Topic 842, “Leases.”