Supplemental Cash Flow Information (Details) - USD ($) $ in Millions			3 Months Ended
		Jan. 01, 2019	Mar. 31, 2020	Mar. 31, 2019
Decrease (increase) in current assets:
Receivables, net			$ 3,397	$ (895)
Inventories			627	28
Prepaid expenses and other			(437)	16
Increase (decrease) in current liabilities:
Accounts payable			(4,222)	1,400
Accrued expenses			(79)	(167)
Taxes other than income taxes payable			(241)	(263)
Income taxes payable			(152)	11
Changes in current assets and current liabilities			(1,107)	130
Cash Flows Related to Interest and Income Taxes
Interest paid in excess of amount capitalized, including interest on finance leases			88	96
Income taxes paid (refunded), net			121	(59)
Cash paid for amounts included in the measurement of lease liabilities:
Operating leases - operating cash flows			106	107
Changes in lease balances resulting from new and modified leases
Operating leases - changes in lease balances resulting from new and modified leases	[1]		92	1,404
Cash paid for amounts included in the measurement of lease liabilities:
Finance leases - operating cash flows			22	11
Finance leases - financing cash flows			15	6
Changes in lease balances resulting from new and modified leases
Finance leases - changes in lease balances resulting from new and modified leases	[1]		1,441	$ 2
Topic 842 [Member]
Changes in lease balances resulting from new and modified leases
Operating leases - changes in lease balances resulting from new and modified leases		$ 1,300
MVP Terminal [Member]
Changes in lease balances resulting from new and modified leases
Finance leases - changes in lease balances resulting from new and modified leases	[1]		$ 1,400

[1] Noncash activity for the three months ended March 31, 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 three months ended March 31, 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.”