Price Risk Management Activities, Effect of Derivative Instruments on Income and Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Commodity Contracts [Member]
Effect of Derivative Instruments on Income
Gain (loss) recognized in other comprehensive income (loss) on derivatives	$ (44)	$ 38	$ (6)
Commodity Contracts [Member] | Revenues [Member]
Effect of Derivative Instruments on Income
Gain (loss) reclassified from accumulated other comprehensive loss into income	(46)	34	2
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	28	0	5
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	(86)	99	(68)
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	54	2	0
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	9	27	(21)
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	$ 44	$ (13)	$ 75