Price Risk Management Activities, Effect of Derivative Instruments on Income and Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Commodity Contracts [Member]
Effect of Derivative Instruments on Income
Gain (loss) recognized in other comprehensive loss	$ (197)	$ 79	$ (71)	$ (215)
Commodity Contracts [Member] | Revenues [Member]
Effect of Derivative Instruments on Income
Gain (loss) reclassified from accumulated other comprehensive loss into income	(119)	10	(3)	(289)
Commodity Contracts [Member] | Revenues [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Effect of Derivative Instruments on Income
Gain (loss) recognized in income on derivatives	(2)	(6)	(19)	(12)
Commodity Contracts [Member] | Cost of Materials and Other [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Effect of Derivative Instruments on Income
Gain (loss) recognized in income on derivatives	(48)	(109)	126	(976)
Commodity Contracts [Member] | Operating Expenses (Excluding Depreciation and Amortization Expense) [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Effect of Derivative Instruments on Income
Gain (loss) recognized in income on derivatives	0	(18)	1	(9)
Foreign Currency Contracts [Member] | Cost of Materials and Other [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Effect of Derivative Instruments on Income
Gain (loss) recognized in income on derivatives	19	57	(1)	104
Foreign Currency Contracts [Member] | Other Income, Net [Member] | Derivatives Not Designated as Hedging Instruments [Member]
Effect of Derivative Instruments on Income
Gain (loss) recognized in income on derivatives	$ 0	$ (38)	$ 0	$ (119)