Hedging Activities and Fair Value Measurements, Recurring Fair Value Measurements (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Financial assets [Abstract]
Value before application of CME Rule 814	$ 1,892	$ 1,232
Impact of CME Rule 814	(1,352)	(993)
Total commodity derivatives	540	239
Total	540	239
Commodity derivatives:
Value before application of CME Rule 814	1,738	1,200
Impact of CME Rule 814	(1,271)	(944)
Total commodity derivatives	467	256
Total	467	256
Net value before application of CME Rule 814 to commodity hedging portfolio	154
Level 1 [Member]
Financial assets [Abstract]
Value before application of CME Rule 814	383	122
Impact of CME Rule 814	(367)	(122)
Total commodity derivatives	16	0
Total	16	0
Commodity derivatives:
Value before application of CME Rule 814	240	199
Impact of CME Rule 814	(224)	(199)
Total commodity derivatives	16	0
Total	16	0
Level 2 [Member]
Financial assets [Abstract]
Value before application of CME Rule 814	1,496	1,110
Impact of CME Rule 814	(985)	(871)
Total commodity derivatives	511	239
Total	511	239
Commodity derivatives:
Value before application of CME Rule 814	1,479	1,001
Impact of CME Rule 814	(1,047)	(745)
Total commodity derivatives	432	256
Total	432	256
Level 3 [Member]
Financial assets [Abstract]
Value before application of CME Rule 814	13	0
Impact of CME Rule 814	0	0
Total commodity derivatives	13	0
Total	13	0
Commodity derivatives:
Value before application of CME Rule 814	19	0
Impact of CME Rule 814	0	0
Total commodity derivatives	19	0
Total	$ 19	$ 0