Supplemental Cash Flow Information (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Decrease (increase) in current assets:
Receivables, net		$ (2,946)	$ 2,968
Inventories		175	627
Prepaid expenses and other		(24)	(8)
Increase (decrease) in current liabilities:
Accounts payable		2,992	(4,222)
Accrued expenses		105	(79)
Taxes other than income taxes payable		(144)	(241)
Income taxes payable		26	(152)
Changes in current assets and current liabilities		184	(1,107)
Cash Flows Related to Interest and Income Taxes
Interest paid in excess of amount capitalized, including interest on finance leases		103	88
Income taxes paid, net		36	121
Operating cash flows
Operating Leases		100	106
Finance Leases		18	22
Financing cash flows
Finance Leases		31	15
Changes in lease balances resulting from new and modified leases, Operating Leases	[1]	72	92
Changes in lease balances resulting from new and modified leases, Finance Leases	[1]	$ 7	1,441
Supplemental Cash Flow Information (Textual)
Decrease in receivables as a result of decrease in commodity prices and sales volumes			3,400
Increase in income taxes receivable			430
MVP Terminal [Member]
Financing cash flows
Changes in lease balances resulting from new and modified leases, Finance Leases			$ 1,400

[1] Noncash activity for the three months ended March 31, 2020 primarily included $1.4 billion for a finance lease right-of-use asset and related liability recognized in connection with the terminaling agreement with MVP.