Supplemental Cash Flow Information (Details) - USD ($) $ in Millions			6 Months Ended
		Jan. 01, 2019	Jun. 30, 2020	Jun. 30, 2019
Decrease (increase) in current assets:
Receivables, net			$ 4,616	$ (1,664)
Inventories			1,136	278
Prepaid expenses and other			(383)	406
Increase (decrease) in current liabilities:
Accounts payable			(5,446)	1,555
Accrued expenses			(73)	(195)
Taxes other than income taxes payable			(180)	(75)
Income taxes payable			(148)	108
Changes in current assets and current liabilities			(478)	413
Cash Flows Related to Interest and Income Taxes
Interest paid in excess of amount capitalized, including interest on finance leases			250	227
Income taxes paid (refunded), net			76	(331)
Operating cash flows
Operating Leases			216	216
Finance Leases			48	25
Financing cash flows
Finance Leases			32	21
Changes in lease balances resulting from new and modified leases, Operating Leases	[1]		163	1,592
Changes in lease balances resulting from new and modified leases, Finance Leases	[1]		1,495	192
Supplemental Cash Flow Information (Textual)
Decrease in receivables as a result of decreases in commodity prices and sales volumes			4,100
Recognition of income tax receivable			440
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]		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 six months ended June 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 six months ended June 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.”