Variable Interest Entities (Details) - USD ($) $ in Millions	Apr. 19, 2021	Mar. 31, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents		$ 2,254	$ 3,313
Property, plant, and equipment, net		30,379	30,389
Liabilities
Current liabilities, including current portion of debt and finance lease obligations		12,307	9,283
Debt and finance lease obligations, less current portion		13,930	13,954
MVP Terminalling, LLC (MVP) [Member] \| Subsequent Event [Member]
Variable Interest Entity (Textual)
Percent membership interest in unconsolidated joint venture sold (percent)	24.99%
Proceeds from sale of membership interest in unconsolidated joint venture	$ 270
Membership percentage in VIE (percent)	25.01%
Variable Interest Entity, Primary Beneficiary [Member]
Assets
Cash and cash equivalents		210	161
Other current assets		292	251
Property, plant, and equipment, net		2,139	1,918
Liabilities
Current liabilities, including current portion of debt and finance lease obligations		806	718
Debt and finance lease obligations, less current portion		25	26
Diamond Green Diesel Holdings LLC (DGD) [Member]
Assets
Cash and cash equivalents		191	144
Other current assets		272	219
Property, plant, and equipment, net		1,431	1,232
Liabilities
Current liabilities, including current portion of debt and finance lease obligations		166	90
Debt and finance lease obligations, less current portion		1	1
Central Mexico Terminals [Member]
Assets
Cash and cash equivalents		0	1
Other current assets		10	24
Property, plant, and equipment, net		614	590
Liabilities
Current liabilities, including current portion of debt and finance lease obligations		632	620
Debt and finance lease obligations, less current portion		0	0
Other VIEs [Member]
Assets
Cash and cash equivalents		19	16
Other current assets		10	8
Property, plant, and equipment, net		94	96
Liabilities
Current liabilities, including current portion of debt and finance lease obligations		8	8
Debt and finance lease obligations, less current portion		$ 24	$ 25

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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