Fair Value Measurements (Reconciliation Of Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	$ 963	$ 226
Total increase (decrease) in unrealized gains included in cost of products sold	1,975	1,746
Purchases	123	37
Sales	(30)	(36)
Settlements	(2,191)	(1,059)
Transfers into Level 3	324	112
Transfers out of Level 3	(228)	(63)
Balance at end of period	936	963
Commodity Derivative Contracts Losses [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	918	199
Total increase (decrease) in unrealized gains included in cost of products sold	1,992	1,729
Purchases	0	0
Sales	0	0
Settlements	(2,191)	(1,059)
Transfers into Level 3	324	112
Transfers out of Level 3	(228)	(63)
Balance at end of period	815	918
Inventory Related Payables [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	11	27
Total increase (decrease) in unrealized gains included in cost of products sold	2	0
Purchases	123	20
Sales	(30)	(36)
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance at end of period	106	11
Long-term Debt
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Sales	0
Settlements	0
Transfers into Level 3	0
Transfers out of Level 3	0
Balance at end of period	15
Long-term Debt | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	34	0
Total increase (decrease) in unrealized gains included in cost of products sold	$ 19	(17)
Purchases		17
Balance at end of period		$ 34