Derivatives and Risk Management Activities - Assets and Liabilities (Details) - Recurring Fair Value Measures - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Derivatives and Risk Management Activities
Total net derivative asset/(liability)	$ (18)	$ (49)
Level 1
Derivatives and Risk Management Activities
Total net derivative asset/(liability)	21	14
Level 2
Derivatives and Risk Management Activities
Total net derivative asset/(liability)	(39)	(63)
Commodity derivatives
Derivatives and Risk Management Activities
Total net derivative asset/(liability)	(43)	(76)
Commodity derivatives \| Level 1
Derivatives and Risk Management Activities
Total net derivative asset/(liability)	21	14
Commodity derivatives \| Level 2
Derivatives and Risk Management Activities
Total net derivative asset/(liability)	(64)	(90)
Interest rate derivatives
Derivatives and Risk Management Activities
Total net derivative asset/(liability)	25	27
Interest rate derivatives \| Level 2
Derivatives and Risk Management Activities
Total net derivative asset/(liability)	$ 25	$ 27