Price Risk Management Activities, Hedging Instruments by Consolidated Balance Sheet Location (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Derivatives Designated as Hedging Instruments [Member] | Commodity Contracts [Member] | Receivable, Net [Member]
Fair Values of Derivative Instruments
Derivative asset, subject to netting	$ 8	$ 12
Derivative liability, subject to netting	8	13
Derivatives Not Designated as Hedging Instruments [Member]
Fair Values of Derivative Instruments
Derivative asset, total	329	398
Derivative liability, total	340	438
Derivatives Not Designated as Hedging Instruments [Member] | Commodity Contracts [Member] | Receivable, Net [Member]
Fair Values of Derivative Instruments
Derivative asset, subject to netting	325	390
Derivative liability, subject to netting	333	435
Derivatives Not Designated as Hedging Instruments [Member] | Physical Purchase Contracts [Member] | Inventories [Member]
Fair Values of Derivative Instruments
Derivative asset, not subject to netting	0	2
Derivative liability, not subject to netting	7	3
Derivatives Not Designated as Hedging Instruments [Member] | Foreign Currency Contracts [Member] | Receivable, Net [Member]
Fair Values of Derivative Instruments
Derivative asset, not subject to netting	4	6
Derivative liability, not subject to netting	$ 0	$ 0