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		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	$ 513	$ 1,939	$ 698	$ 936
Total increase (decrease) in unrealized losses included in cost of products sold	538	272	774	1,661
Purchases	5	7	7	9
Sales	0	(3)	0	(56)
Settlements	(286)	(1,251)	(741)	(1,729)
Transfers into Level 3	88	161	126	322
Transfers out of Level 3	(2)	(99)	(8)	(117)
Balance at end of period	856	1,026	856	1,026
Long-term Debt [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	1	30	6	15
Total increase (decrease) in unrealized losses included in cost of products sold	(1)	(19)	(6)	(4)
Purchases	0	0	0	0
Balance at end of period	0	11	0	11
Inventory Related Payables [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	57	53	89	106
Total increase (decrease) in unrealized losses included in cost of products sold	4	(2)	2	(4)
Purchases	5	7	7	9
Sales	0	(3)	0	(56)
Settlements	(3)	0	(34)	0
Transfers into Level 3	2	0	1	0
Transfers out of Level 3	0	0	0	0
Balance at end of period	65	55	65	55
Commodity Derivative Contracts Losses [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	455	1,856	603	815
Total increase (decrease) in unrealized losses included in cost of products sold	535	293	778	1,669
Purchases	0	0	0	0
Sales	0	0	0	0
Settlements	(283)	(1,251)	(707)	(1,729)
Transfers into Level 3	86	161	125	322
Transfers out of Level 3	(2)	(99)	(8)	(117)
Balance at end of period	$ 791	$ 960	$ 791	$ 960