Fair Value Measurements (Reconciliation Of Liabilities Measured At Fair Value On A Recurring Basis) (Details) - Significant Unobservable Inputs (Level 3) [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	$ 698	$ 936
Total increase (decrease) in unrealized losses included in cost of products sold	236	1,389
Purchases	2	2
Sales	0	(53)
Settlements	(455)	(478)
Transfers into Level 3	39	161
Transfers out of Level 3	(7)	(18)
Balance at end of period	513	1,939
Long-term Debt [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	6	15
Total increase (decrease) in unrealized losses included in cost of products sold	(5)	15
Purchases	0	0
Balance at end of period	1	30
Inventory Related Payables [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	89	106
Total increase (decrease) in unrealized losses included in cost of products sold	(2)	(2)
Purchases	2	2
Sales	0	(53)
Settlements	(31)	0
Transfers into Level 3	0	0
Transfers out of Level 3	(1)	0
Balance at end of period	57	53
Commodity Derivative Contracts Losses [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	603	815
Total increase (decrease) in unrealized losses included in cost of products sold	243	1,376
Purchases	0	0
Sales	0	0
Settlements	(424)	(478)
Transfers into Level 3	39	161
Transfers out of Level 3	(6)	(18)
Balance at end of period	$ 455	$ 1,856