Variable Interest Entities, Consolidated (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 3,313	$ 2,583
Property, plant, and equipment, net	30,389	29,264
Liabilities
Current liabilities, including current portion of debt and finance lease obligations	9,283	13,160
Debt and finance lease obligations, less current portion	13,954	9,178
Variable Interest Entity, Primary Beneficiary [Member]
Assets
Cash and cash equivalents	161	110
Other current assets	251	689
Property, plant, and equipment, net	1,918	1,192
Liabilities
Current liabilities, including current portion of debt and finance lease obligations	718	483
Debt and finance lease obligations, less current portion	26	31
Diamond Green Diesel Holdings LLC (DGD) [Member]
Assets
Cash and cash equivalents	144	85
Other current assets	219	567
Property, plant, and equipment, net	1,232	706
Liabilities
Current liabilities, including current portion of debt and finance lease obligations	90	66
Debt and finance lease obligations, less current portion	$ 1	0
Variable Interest Entity (Textual)
Ownership interest (percent)	50.00%
Central Mexico Terminals [Member]
Assets
Cash and cash equivalents	$ 1	0
Other current assets	24	33
Property, plant, and equipment, net	590	381
Liabilities
Current liabilities, including current portion of debt and finance lease obligations	620	409
Debt and finance lease obligations, less current portion	0	0
Other VIEs [Member]
Assets
Cash and cash equivalents	16	25
Other current assets	8	89
Property, plant, and equipment, net	96	105
Liabilities
Current liabilities, including current portion of debt and finance lease obligations	8	8
Debt and finance lease obligations, less current portion	$ 25	$ 31
Variable Interest Entity (Textual)
Ownership interest (percent)	50.00%

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