Hedging Activities and Fair Value Measurements, Recurring Fair Value Measurements (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Financial assets [Abstract]
Value before application of CME Rule 814	$ 1,619	$ 1,232
Impact of CME Rule 814	(1,246)	(993)
Total commodity derivatives	373	239
Total	373	239
Commodity derivatives:
Value before application of CME Rule 814	1,711	1,200
Impact of CME Rule 814	(1,299)	(944)
Total commodity derivatives	412	256
Total	412	256
Net value before application of CME Rule 814 to commodity hedging portfolio	(92)
Level 1 [Member]
Financial assets [Abstract]
Value before application of CME Rule 814	356	122
Impact of CME Rule 814	(328)	(122)
Total commodity derivatives	28	0
Total	28	0
Commodity derivatives:
Value before application of CME Rule 814	505	199
Impact of CME Rule 814	(476)	(199)
Total commodity derivatives	29	0
Total	29	0
Level 2 [Member]
Financial assets [Abstract]
Value before application of CME Rule 814	1,250	1,110
Impact of CME Rule 814	(918)	(871)
Total commodity derivatives	332	239
Total	332	239
Commodity derivatives:
Value before application of CME Rule 814	1,185	1,001
Impact of CME Rule 814	(823)	(745)
Total commodity derivatives	362	256
Total	362	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	21	0
Impact of CME Rule 814	0	0
Total commodity derivatives	21	0
Total	$ 21	$ 0