Fair Value Measurements (Fair Value Measurements At Reporting Date) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Assets:
Derivative Asset	$ 2,619	$ 3,108
Liabilities:
Derivative Liability	2,128	2,584
Fair Value, Recurring [Member]
Assets:
Inventories carried at market	9,003	7,941
Cash Equivalents, at Carrying Value	302	297
Available-for-sale Securities, Fair Value Disclosure		1
Restricted Investments, at Fair Value	995	1,067
Total Assets	12,919	12,414
Liabilities:
Inventory-related payables	1,172	509
Total Liabilities	3,354	3,127
Fair Value, Recurring [Member] | Commodity Contracts [Member]
Assets:
Derivative Asset	2,274	2,764
Liabilities:
Derivative Liability	1,813	2,034
Fair Value, Recurring [Member] | Foreign Exchange Contracts [Member]
Assets:
Derivative Asset	215	283
Liabilities:
Derivative Liability	313	535
Fair Value, Recurring [Member] | Interest Rate Contracts [Member]
Assets:
Derivative Asset	130	61
Liabilities:
Derivative Liability	2	15
Fair Value, Recurring [Member] | Embedded Derivative Financial Instruments [Member]
Liabilities:
Derivative Liability	54	34
Fair Value, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Assets:
Inventories carried at market	0	0
Cash Equivalents, at Carrying Value	302	297
Available-for-sale Securities, Fair Value Disclosure		1
Restricted Investments, at Fair Value	995	1,067
Total Assets	1,297	1,365
Liabilities:
Inventory-related payables	0	0
Total Liabilities	0	0
Fair Value, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Commodity Contracts [Member]
Assets:
Derivative Asset	0	0
Liabilities:
Derivative Liability	0	0
Fair Value, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Foreign Exchange Contracts [Member]
Assets:
Derivative Asset	0	0
Liabilities:
Derivative Liability	0	0
Fair Value, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Interest Rate Contracts [Member]
Assets:
Derivative Asset	0	0
Liabilities:
Derivative Liability	0	0
Fair Value, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Embedded Derivative Financial Instruments [Member]
Liabilities:
Derivative Liability	0	0
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Inventories carried at market	5,933	5,758
Cash Equivalents, at Carrying Value	0	0
Available-for-sale Securities, Fair Value Disclosure		0
Restricted Investments, at Fair Value	0	0
Total Assets	7,868	8,007
Liabilities:
Inventory-related payables	1,151	498
Total Liabilities	2,620	2,164
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Commodity Contracts [Member]
Assets:
Derivative Asset	1,590	1,905
Liabilities:
Derivative Liability	1,165	1,116
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Foreign Exchange Contracts [Member]
Assets:
Derivative Asset	215	283
Liabilities:
Derivative Liability	302	535
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Interest Rate Contracts [Member]
Assets:
Derivative Asset	130	61
Liabilities:
Derivative Liability	2	15
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Embedded Derivative Financial Instruments [Member]
Liabilities:
Derivative Liability	0	0
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Inventories carried at market	3,070	2,183
Cash Equivalents, at Carrying Value	0	0
Available-for-sale Securities, Fair Value Disclosure		0
Restricted Investments, at Fair Value	0	0
Total Assets	3,754	3,042
Liabilities:
Inventory-related payables	21	11
Total Liabilities	734	963
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Commodity Contracts [Member]
Assets:
Derivative Asset	684	859
Liabilities:
Derivative Liability	648	918
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Foreign Exchange Contracts [Member]
Assets:
Derivative Asset	0	0
Liabilities:
Derivative Liability	11	0
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Interest Rate Contracts [Member]
Assets:
Derivative Asset	0	0
Liabilities:
Derivative Liability	0	0
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Embedded Derivative Financial Instruments [Member]
Liabilities:
Derivative Liability	$ 54	$ 34