Derivatives and Risk Management Activities - Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Recurring Fair Value Measurements
Total net derivative asset/(liability)	$ 191	$ 4
Level 1
Recurring Fair Value Measurements
Total net derivative asset/(liability)	99	(2)
Level 2
Recurring Fair Value Measurements
Total net derivative asset/(liability)	92	6
Commodity derivatives
Recurring Fair Value Measurements
Total net derivative asset/(liability)	130	(4)
Commodity derivatives \| Level 1
Recurring Fair Value Measurements
Total net derivative asset/(liability)	99	(2)
Commodity derivatives \| Level 2
Recurring Fair Value Measurements
Total net derivative asset/(liability)	31	(2)
Foreign currency derivatives
Recurring Fair Value Measurements
Total net derivative asset/(liability)	61	8
Foreign currency derivatives \| Level 1
Recurring Fair Value Measurements
Total net derivative asset/(liability)	0	0
Foreign currency derivatives \| Level 2
Recurring Fair Value Measurements
Total net derivative asset/(liability)	$ 61	$ 8