Fair Value Measurements (Reconciliation Of Assets Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 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	1,892	2,515
Purchases	29,929	49,735
Sales	(30,038)	(50,414)
Settlements	(1,563)	(1,672)
Transfers into Level 3	1,955	1,488
Transfers out of Level 3	(2,032)	(1,815)
Balance at end of period	$ 3,444	$ 3,301
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Cost of products sold	Cost of products sold
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Cost of products sold	Cost of products sold
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	432	867
Purchases	29,929	49,735
Sales	(30,038)	(50,414)
Settlements	(4)
Transfers into Level 3	1,584	1,088
Transfers out of Level 3	(1,950)	(1,520)
Balance at end of period	2,713	2,760
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	1,460	1,648
Settlements	(1,559)	(1,672)
Transfers into Level 3	371	400
Transfers out of Level 3	(82)	(295)
Balance at end of period	$ 731	$ 541