Fair Value Measurements (Reconciliation Of Assets 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, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	$ 3,301	$ 3,464
Total increase (decrease) in unrealized gains included in cost of products sold	479	1,280
Purchases	8,665	9,552
Sales	(8,254)	(9,315)
Settlements	(382)	(276)
Transfers into Level 3	655	350
Transfers out of Level 3	(312)	(268)
Balance at end of period	4,152	4,787
Inventories Carried At Market [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	2,760	3,004
Total increase (decrease) in unrealized gains included in cost of products sold	2	647
Purchases	8,665	9,552
Sales	(8,254)	(9,315)
Settlements	0	0
Transfers into Level 3	605	327
Transfers out of Level 3	(275)	(256)
Balance at end of period	3,503	3,959
Commodity Derivative Contracts Gains [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	541	460
Total increase (decrease) in unrealized gains included in cost of products sold	477	633
Purchases	0	0
Sales	0	0
Settlements	(382)	(276)
Transfers into Level 3	50	23
Transfers out of Level 3	(37)	(12)
Balance at end of period	$ 649	$ 828